diff --git a/.github/workflows/check-standard.yaml b/.github/workflows/check-standard.yaml
index 524fb30..7f99670 100644
--- a/.github/workflows/check-standard.yaml
+++ b/.github/workflows/check-standard.yaml
@@ -26,8 +26,6 @@ jobs:
         config:
           - {os: windows-latest, r: 'release'}
           - {os: macOS-latest, r: 'release'}
-          - {os: ubuntu-20.04, r: '3.5', repos: "https://packagemanager.rstudio.com/cran/__linux__/focal/latest"}
-          - {os: ubuntu-20.04, r: '3.6', repos: "https://packagemanager.rstudio.com/cran/__linux__/focal/latest"}
           - {os: ubuntu-20.04, r: 'release', rspm: "https://packagemanager.rstudio.com/cran/__linux__/focal/latest"}
           - {os: ubuntu-20.04, r: 'devel', rspm: "https://packagemanager.rstudio.com/cran/__linux__/focal/latest"}
 
diff --git a/DESCRIPTION b/DESCRIPTION
index f532941..f34b3ab 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: metacore
 Title: A Centralized Metadata Object Focus on Clinical Trial Data Programming Workflows
-Version: 0.1.2
+Version: 0.1.3
 Authors@R: 
     c(person(given = "Christina",
              family = "Fillmore",
@@ -27,7 +27,9 @@ Description: Create an immutable container holding metadata for the purpose of b
 License: MIT + file LICENSE
 Encoding: UTF-8
 Roxygen: list(markdown = TRUE, r6 = FALSE)
-RoxygenNote: 7.2.1
+RoxygenNote: 7.3.1
+Depends: 
+    R (>= 3.6)
 Suggests: 
     testthat,
     knitr,
diff --git a/R/metacore.R b/R/metacore.R
index 1f804c0..68be91f 100644
--- a/R/metacore.R
+++ b/R/metacore.R
@@ -189,14 +189,17 @@ MetaCore_filter <- function(value) {
                  multiple = "all") %>%
       distinct(variable, .keep_all = TRUE) # for when duplicates gett through and have different lables but the same name
 
+   # Get values/variables that need derivations
+   val_deriv <- private$.value_spec %>%
+      distinct(.data$derivation_id) %>%
+      na.omit()
+
    private$.derivations <- private$.derivations %>%
-      right_join(private$.value_spec %>%
-                    select(derivation_id) %>%
-                    na.omit(), by = "derivation_id", multiple = "all")
+      right_join(val_deriv, by = "derivation_id", multiple = "all")
 
    private$.codelist <- private$.codelist %>%
       right_join(private$.value_spec %>%
-                    select(code_id) %>%
+                    distinct(.data$code_id) %>%
                     na.omit(), by = "code_id", multiple = "all")
 
    private$.supp <- private$.supp %>% filter(dataset == value)
@@ -330,13 +333,13 @@ select_dataset <- function(.data, dataset, simplify = FALSE) {
 
    if (simplify) {
 
-      suppressMessages(
+     test <-  suppressMessages(
          list(
             cl$ds_vars,
             cl$var_spec,
             cl$value_spec,
             cl$derivations,
-            cl$codelist,
+            select(cl$codelist, code_id, codes),
             cl$supp
          ) %>%
             reduce(left_join)
diff --git a/R/spec_builder.R b/R/spec_builder.R
index f011687..b746436 100644
--- a/R/spec_builder.R
+++ b/R/spec_builder.R
@@ -2,8 +2,8 @@
 #'
 #' This function takes the location of an excel specification document and reads
 #' it in as a meta core object. At the moment it only supports specification in
-#' the format of pinnacle 21 specifications. But, the @family spec builder can
-#' be used as building blocks for bespoke specification documents
+#' the format of pinnacle 21 specifications. But, the section level spec builder can
+#' be used as building blocks for bespoke specification documents.
 #'
 #' @param path string of file location
 #' @param quiet Option to quietly load in, this will suppress warnings, but not
@@ -96,7 +96,7 @@ read_all_sheets <- function(path){
 #' @return a dataset formatted for the metacore object
 #' @export
 #'
-#' @family spec builder
+#' @family {spec builder}
 spec_type_to_ds_spec <- function(doc, cols = c("dataset" = "[N|n]ame|[D|d]ataset|[D|d]omain",
                                                "structure" = "[S|s]tructure",
                                                "label" = "[L|l]abel|[D|d]escription"), sheet = NULL){
@@ -140,7 +140,7 @@ spec_type_to_ds_spec <- function(doc, cols = c("dataset" = "[N|n]ame|[D|d]ataset
 #' @return a dataset formatted for the metacore object
 #' @export
 #'
-#' @family spec builder
+#' @family {spec builder}
 spec_type_to_ds_vars <- function(doc, cols = c("dataset" = "[D|d]ataset|[D|d]omain",
                                                "variable" = "[V|v]ariable [[N|n]ame]?|[V|v]ariables?",
                                                "order" = "[V|v]ariable [O|o]rder|[O|o]rder",
@@ -214,7 +214,7 @@ spec_type_to_ds_vars <- function(doc, cols = c("dataset" = "[D|d]ataset|[D|d]oma
 #' @return a dataset formatted for the metacore object
 #' @export
 #'
-#' @family spec builder
+#' @family {spec builder}
 spec_type_to_var_spec <- function(doc, cols = c("variable" = "[N|n]ame|[V|v]ariables?",
                                                 "length" = "[L|l]ength",
                                                 "label" = "[L|l]abel",
@@ -314,7 +314,7 @@ spec_type_to_var_spec <- function(doc, cols = c("variable" = "[N|n]ame|[V|v]aria
 #' @return a dataset formatted for the metacore object
 #' @export
 #'
-#' @family spec builder
+#' @family {spec builder}
 spec_type_to_value_spec <- function(doc, cols = c("dataset" = "[D|d]ataset|[D|d]omain",
                                                   "variable" = "[N|n]ame|[V|v]ariables?",
                                                   "origin" = "[O|o]rigin",
@@ -408,7 +408,10 @@ spec_type_to_value_spec <- function(doc, cols = c("dataset" = "[D|d]ataset|[D|d]
 
    if(!"derivation_id" %in% names(cols)){
       out <- out %>%
-         mutate(derivation_id = paste0(dataset, ".", variable))
+         mutate(derivation_id =
+                   if_else(str_to_lower(.data$origin) == "assigned",
+                      paste0(dataset, ".", variable),
+                      paste0("pred.", dataset, ".", variable)))
    }
 
    # Get missing columns
@@ -421,7 +424,7 @@ spec_type_to_value_spec <- function(doc, cols = c("dataset" = "[D|d]ataset|[D|d]
       mutate(sig_dig = as.integer(.data$sig_dig),
              derivation_id = case_when(
                 !is.na(.data$derivation_id) ~ .data$derivation_id,
-                str_to_lower(.data$origin) == "predecessor" ~ as.character(.data$predecessor),
+                str_to_lower(.data$origin) == "predecessor" ~ paste0("pred.", as.character(.data$predecessor)),
                 str_to_lower(.data$origin) == "assigned" ~ paste0(.data$dataset, ".", .data$variable))
       ) %>%
       select(-.data$predecessor)
@@ -453,7 +456,7 @@ spec_type_to_value_spec <- function(doc, cols = c("dataset" = "[D|d]ataset|[D|d]
 #' @return a dataset formatted for the metacore object
 #' @export
 #'
-#' @family spec builder
+#' @family {spec builder}
 spec_type_to_codelist <- function(doc, codelist_cols = c("code_id" = "ID",
                                                          "name" = "[N|n]ame",
                                                          "code" = "^[C|c]ode|^[T|t]erm",
@@ -558,7 +561,7 @@ spec_type_to_codelist <- function(doc, codelist_cols = c("code_id" = "ID",
 #' @return a dataset formatted for the metacore object
 #' @export
 #'
-#' @family spec builder
+#' @family {spec builder}
 #' @importFrom purrr quietly
 spec_type_to_derivations <- function(doc, cols = c("derivation_id" = "ID",
                                                    "derivation" = "[D|d]efinition|[D|d]escription"),
@@ -587,11 +590,25 @@ spec_type_to_derivations <- function(doc, cols = c("derivation_id" = "ID",
    if(class(ls_derivations)[1] == "list"){
       ls_derivations <- ls_derivations %>%
          reduce(bind_rows)
+      # Get the comments
+      if(any(str_detect(names(doc), "[C|c]omment"))){
+         comments <- doc[str_detect(names(doc), "[C|c]omment")][[1]] |>
+            select(matches("ID|Description"))
+         with_comments <- ls_derivations |>
+            filter(str_to_lower(.data$origin) == "assigned") |>
+            left_join(comments, by = c("comment" = "ID" )) |>
+            mutate(comment = .data$Description) |>
+            select(-.data$Description)
+         ls_derivations <- ls_derivations |>
+            filter(str_to_lower(.data$origin) != "assigned") |>
+            bind_rows(with_comments)
+      }
    }
+
    other_derivations <- ls_derivations %>%
       mutate(
          derivation_id = case_when(
-            str_to_lower(.data$origin) == "predecessor" ~ as.character(.data$predecessor),
+            str_to_lower(.data$origin) == "predecessor" ~ paste0("pred.", as.character(.data$predecessor)),
             str_to_lower(.data$origin) == "assigned" ~ paste0(.data$dataset, ".", .data$variable),
             TRUE ~ NA_character_
             ),
diff --git a/R/xml_builders.R b/R/xml_builders.R
index 8526098..f3e6ae6 100644
--- a/R/xml_builders.R
+++ b/R/xml_builders.R
@@ -357,8 +357,12 @@ xml_to_codelist <- function(doc) {
             version = xml_attr(node, "Version"),
             type = "external_library"
          )
-      }) %>%
-      nest(codes = c(.data$dictionary, .data$version))
+      })
+   if(nrow(external_libs) > 0){
+      external_libs <- external_libs |>
+         nest(codes = c(.data$dictionary, .data$version))
+   }
+
 
    # Combinging the code decode with the permitted values
    bind_rows(code_decode, permitted_val, external_libs) %>%
diff --git a/man/get_control_term.Rd b/man/get_control_term.Rd
index 3171bdd..d5317a4 100644
--- a/man/get_control_term.Rd
+++ b/man/get_control_term.Rd
@@ -24,7 +24,9 @@ lists) for a given variable. The dataset can be optionally specified if there
 is different control terminology for different datasets
 }
 \examples{
+\dontrun{
 meta_ex <- spec_to_metacore(metacore_example("p21_mock.xlsx"))
 get_control_term(meta_ex, QVAL, SUPPAE)
 get_control_term(meta_ex, "QVAL", "SUPPAE")
 }
+}
diff --git a/man/spec_to_metacore.Rd b/man/spec_to_metacore.Rd
index f994fca..cc4cfdd 100644
--- a/man/spec_to_metacore.Rd
+++ b/man/spec_to_metacore.Rd
@@ -21,6 +21,6 @@ given a spec document it returns a metacore object
 \description{
 This function takes the location of an excel specification document and reads
 it in as a meta core object. At the moment it only supports specification in
-the format of pinnacle 21 specifications. But, the @family spec builder can
-be used as building blocks for bespoke specification documents
+the format of pinnacle 21 specifications. But, the section level spec builder can
+be used as building blocks for bespoke specification documents.
 }
diff --git a/man/spec_type_to_codelist.Rd b/man/spec_type_to_codelist.Rd
index f4ebb9d..91646ec 100644
--- a/man/spec_type_to_codelist.Rd
+++ b/man/spec_type_to_codelist.Rd
@@ -47,11 +47,11 @@ sheet input). The named vector \verb{*_cols} is used to determine which is the
 correct sheet and renames the columns.
 }
 \seealso{
-Other spec builder: 
+Other {spec builder}: 
 \code{\link{spec_type_to_derivations}()},
 \code{\link{spec_type_to_ds_spec}()},
 \code{\link{spec_type_to_ds_vars}()},
 \code{\link{spec_type_to_value_spec}()},
 \code{\link{spec_type_to_var_spec}()}
 }
-\concept{spec builder}
+\concept{{spec builder}}
diff --git a/man/spec_type_to_derivations.Rd b/man/spec_type_to_derivations.Rd
index 9d90625..eca35fc 100644
--- a/man/spec_type_to_derivations.Rd
+++ b/man/spec_type_to_derivations.Rd
@@ -36,11 +36,11 @@ correct sheet and renames the columns. The derivation will be used for
 "predecessor" origins.
 }
 \seealso{
-Other spec builder: 
+Other {spec builder}: 
 \code{\link{spec_type_to_codelist}()},
 \code{\link{spec_type_to_ds_spec}()},
 \code{\link{spec_type_to_ds_vars}()},
 \code{\link{spec_type_to_value_spec}()},
 \code{\link{spec_type_to_var_spec}()}
 }
-\concept{spec builder}
+\concept{{spec builder}}
diff --git a/man/spec_type_to_ds_spec.Rd b/man/spec_type_to_ds_spec.Rd
index f99d3a5..30f135d 100644
--- a/man/spec_type_to_ds_spec.Rd
+++ b/man/spec_type_to_ds_spec.Rd
@@ -29,11 +29,11 @@ input). The named vector \code{cols} is used to determine which is the correct
 sheet and renames the columns
 }
 \seealso{
-Other spec builder: 
+Other {spec builder}: 
 \code{\link{spec_type_to_codelist}()},
 \code{\link{spec_type_to_derivations}()},
 \code{\link{spec_type_to_ds_vars}()},
 \code{\link{spec_type_to_value_spec}()},
 \code{\link{spec_type_to_var_spec}()}
 }
-\concept{spec builder}
+\concept{{spec builder}}
diff --git a/man/spec_type_to_ds_vars.Rd b/man/spec_type_to_ds_vars.Rd
index 9b0bd29..8d493b9 100644
--- a/man/spec_type_to_ds_vars.Rd
+++ b/man/spec_type_to_ds_vars.Rd
@@ -39,11 +39,11 @@ input). The named vector \code{cols} is used to determine which is the correct
 sheet and renames the columns
 }
 \seealso{
-Other spec builder: 
+Other {spec builder}: 
 \code{\link{spec_type_to_codelist}()},
 \code{\link{spec_type_to_derivations}()},
 \code{\link{spec_type_to_ds_spec}()},
 \code{\link{spec_type_to_value_spec}()},
 \code{\link{spec_type_to_var_spec}()}
 }
-\concept{spec builder}
+\concept{{spec builder}}
diff --git a/man/spec_type_to_value_spec.Rd b/man/spec_type_to_value_spec.Rd
index f9a1a59..84c4ab3 100644
--- a/man/spec_type_to_value_spec.Rd
+++ b/man/spec_type_to_value_spec.Rd
@@ -48,11 +48,11 @@ sheet input). The named vector \code{cols} is used to determine which is the
 correct sheet and renames the columns
 }
 \seealso{
-Other spec builder: 
+Other {spec builder}: 
 \code{\link{spec_type_to_codelist}()},
 \code{\link{spec_type_to_derivations}()},
 \code{\link{spec_type_to_ds_spec}()},
 \code{\link{spec_type_to_ds_vars}()},
 \code{\link{spec_type_to_var_spec}()}
 }
-\concept{spec builder}
+\concept{{spec builder}}
diff --git a/man/spec_type_to_var_spec.Rd b/man/spec_type_to_var_spec.Rd
index 04e8964..ba02179 100644
--- a/man/spec_type_to_var_spec.Rd
+++ b/man/spec_type_to_var_spec.Rd
@@ -30,11 +30,11 @@ input). The named vector \code{cols} is used to determine which is the correct
 sheet and renames the columns. (Note: the keep column will be converted logical)
 }
 \seealso{
-Other spec builder: 
+Other {spec builder}: 
 \code{\link{spec_type_to_codelist}()},
 \code{\link{spec_type_to_derivations}()},
 \code{\link{spec_type_to_ds_spec}()},
 \code{\link{spec_type_to_ds_vars}()},
 \code{\link{spec_type_to_value_spec}()}
 }
-\concept{spec builder}
+\concept{{spec builder}}
diff --git a/tests/testthat/test-reader.R b/tests/testthat/test-reader.R
index e1860e6..d4c2623 100644
--- a/tests/testthat/test-reader.R
+++ b/tests/testthat/test-reader.R
@@ -255,10 +255,18 @@ test_that("Test var_spec readers", {
    spec_var_spec <- spec_type_to_var_spec(spec) %>%
       arrange(variable) %>%
       select(variable, type, length, label, format)
-   # remove common as it is derived when reading in specs but left alone from defines
+
+   spec2 <- spec
+   spec2$Variables |>
+      select(-Dataset)
+   no_ds <- spec_type_to_var_spec(spec2) |>
+      arrange(variable) %>%
+      select(variable, type, length, label, format)
+   expect_equal(no_ds, spec_var_spec)
 
    # Tests
    expect_equal(def_var_spec, ref_var_spec)
+   # remove common as it is derived when reading in specs but left alone from defines
    expect_equal(spec_var_spec,
                 ref_var_spec %>%
                    select(-common))
@@ -397,7 +405,6 @@ test_that("values_spec reader tests", {
                 map(~paste0(.[1], " '", .[2])),
              where = if_else(where == "NA 'NA", NA_character_, paste0(where, "'")))
 
-
    # Tests
    expect_equal(def_value_spec, ref_value_spec)
    expect_equal(spec_value_spec,  ref_value_spec)
@@ -466,10 +473,12 @@ test_that("derivation reader tests", {
       select(derivation_id = ID,
              derivation = Description) %>%
       mutate(derivation_id = paste0("MT.", derivation_id))
+
    ref_deriv <- spec$Variables %>%
       filter(Origin %in% c("Assigned")) %>%
+      left_join(select(spec$Comments, ID, Description), by = c("Comment" = "ID")) %>%
       mutate(derivation_id = paste0("MT.", Dataset, ".", Variable),
-             derivation = Comment) %>%
+             derivation = Description) %>%
       select(starts_with("derivation")) %>%
       bind_rows(ref_deriv, .) %>%
       arrange(derivation_id) %>%