diff --git a/accessibility-checker-engine/karma.conf.js b/accessibility-checker-engine/karma.conf.js
index 62a4bb4f2..9ba11327a 100644
--- a/accessibility-checker-engine/karma.conf.js
+++ b/accessibility-checker-engine/karma.conf.js
@@ -48,10 +48,11 @@
                 //{ pattern: 'test/v2/checker/accessibility/rules/aria_role_valid_ruleunit/td_attribute_invalid_copy.html', watched: true },
                 //{ pattern: 'test/v2/checker/accessibility/rules/text_block_heading_ruleunit/Headings-noneUsedEmphasizedText.html', watched: true },
                 { pattern: 'test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass.html', watched: true },
+                { pattern: 'test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass2.html', watched: true },
     
     
-                //{ pattern: 'test/**/*_ruleunit/*.html', watched: true },
-                //{ pattern: 'test/**/*_ruleunit/*.htm', watched: true },
+                { pattern: 'test/**/*_ruleunit/*.html', watched: true },
+                { pattern: 'test/**/*_ruleunit/*.htm', watched: true },
                 // all files ending in "_test"
                 // { pattern: 'test/*_test.js', watched: true },
                 { pattern: 'test/**/*_test.js', watched: true }
diff --git a/accessibility-checker-engine/src/v2/common/Engine.ts b/accessibility-checker-engine/src/v2/common/Engine.ts
index 03e25f7ec..ba4da390a 100644
--- a/accessibility-checker-engine/src/v2/common/Engine.ts
+++ b/accessibility-checker-engine/src/v2/common/Engine.ts
@@ -163,7 +163,7 @@ export class Engine implements IEngine {
         }
         root.ownerDocument && ((root.ownerDocument as any).PT_CHECK_HIDDEN_CONTENT = false);
         CacheUtil.clearCaches(root);
-        const walker = new DOMWalker(root, false, root, true);
+        const walker = new DOMWalker(root, false, root, true, false);
         const retVal : Report = {
             results: [],
             numExecuted: 0,
diff --git a/accessibility-checker-engine/src/v2/dom/DOMWalker.ts b/accessibility-checker-engine/src/v2/dom/DOMWalker.ts
index 92222e070..5fcbac6bf 100644
--- a/accessibility-checker-engine/src/v2/dom/DOMWalker.ts
+++ b/accessibility-checker-engine/src/v2/dom/DOMWalker.ts
@@ -25,8 +25,10 @@ export class DOMWalker {
     node : Node;
     bEndTag: boolean;
     considerHidden: boolean;
+    DEBUG: boolean;
 
-    constructor(element : Node, bEnd? : boolean, root? : Node, considerHidden? : boolean) {
+    constructor(element : Node, bEnd? : boolean, root? : Node, considerHidden? : boolean, DEBUG?: boolean) {
+        this.DEBUG = !!DEBUG;
         this.root = root || ((element && element.ownerDocument) ? element.ownerDocument.documentElement: element);
         if (this.root.nodeType === 9) {
             this.root = (this.root as Document).documentElement
@@ -82,7 +84,11 @@ export class DOMWalker {
         }
     }
 
+    DEBUGIDX = 0;
+    indent = 0;
     nextNode() : boolean {
+        let DBG = false;//this.DEBUGIDX >= 7 && this.DEBUGIDX <= 10;
+        let startName = this.node.nodeName;
         if (!this.node) {
             this.bEndTag = false;
             return false;
@@ -99,6 +105,7 @@ export class DOMWalker {
                     && iframeNode.contentDocument
                     && iframeNode.contentDocument.documentElement)
                 {
+                    DBG && console.log("!!!0a");
                     let ownerElement = this.node;
                     this.node = iframeNode.contentDocument.documentElement;
                     (this.node as any).ownerElement = ownerElement;
@@ -107,6 +114,7 @@ export class DOMWalker {
                     && elementNode.shadowRoot
                     && elementNode.shadowRoot.firstChild)
                 {
+                    DBG && console.log("!!!0b");
                     let ownerElement = this.node;
                     this.node = elementNode.shadowRoot;
                     (this.node as any).ownerElement = ownerElement;
@@ -114,24 +122,30 @@ export class DOMWalker {
                     && elementNode.nodeName.toLowerCase() === "slot"
                     && slotElement.assignedNodes().length > 0) 
                 {
+                    DBG && console.log("!!!0c");
                     let slotOwner = this.node;
                     this.node = slotElement.assignedNodes()[0];
                     (this.node as any).slotOwner = slotOwner;
                     (this.node as any).slotIndex = 0;
-                } else if ((this.node.nodeType === 1 /* Node.ELEMENT_NODE */ || this.node.nodeType === 11 /* Node.DOCUMENT_FRAGMENT_NODE */) && this.node.firstChild) {
+                } else if ((this.node.nodeType === 1 /* Node.ELEMENT_NODE */ || this.node.nodeType === 11 /* Node.DOCUMENT_FRAGMENT_NODE */) && this.node.firstChild && !(this.node.firstChild as any).slotOwner) {
+                    DBG && console.log("!!!0d");
                     this.node = this.node.firstChild;
                 } else {
+                    DBG && console.log("!!!0e");
                     this.bEndTag = true;
                 }
             } else {
+                DBG && console.log("!!!1");
                 if (this.atRoot()) {
+                    DBG && console.log("!!!1a");
                     return false;
                 } else if ((this.node as any).slotOwner) {
+                    DBG && console.log("!!!1b");
                     let slotOwner = (this.node as any).slotOwner;
                     let nextSlotIndex = (this.node as any).slotIndex+1;
-                    delete (this.node as any).slotOwner;
-                    delete (this.node as any).slotIndex;
-                    if (nextSlotIndex < slotOwner.assignedNodes().length) {
+                    // delete (this.node as any).slotOwner;
+                    // delete (this.node as any).slotIndex;
+                     if (nextSlotIndex < slotOwner.assignedNodes().length) {
                         this.node = slotOwner.assignedNodes()[nextSlotIndex];
                         (this.node as any).slotOwner = slotOwner;
                         (this.node as any).slotIndex = nextSlotIndex;    
@@ -141,15 +155,19 @@ export class DOMWalker {
                         this.bEndTag = true;
                     }
                 } else if ((this.node as any).ownerElement) {
+                    DBG && console.log("!!!1c");
                     this.node = (this.node as any).ownerElement;
                     this.bEndTag = true;
                 } else if (this.node.nextSibling) {
+                    DBG && console.log("!!!1d");
                     this.node = this.node.nextSibling;
                     this.bEndTag = false;
                 } else if (this.node.parentNode) {
+                    DBG && console.log("!!!1e");
                     this.node = this.node.parentNode;
                     this.bEndTag = true;
                 } else {
+                    DBG && console.log("!!!f");
                     return false;
                 }
             }
@@ -157,6 +175,19 @@ export class DOMWalker {
             (this.node.nodeType !== 1 && this.node.nodeType !== 11 && this.node.nodeType !== 3 )
             || (this.node.nodeType === 1 && (this.node as Element).getAttribute("aChecker") === "ACE")
         );
+        const indent = () => {
+            let s = "";
+            for (let idx=0; idx<this.indent; ++idx) {
+                s += " ";
+            }
+            return s;
+        }
+        if (this.bEndTag) this.indent -= 2;
+        this.DEBUG && console.log(indent()+`<${this.bEndTag?"/":""}${this.node.nodeName}> (from ${startName}) ${this.DEBUGIDX++}`);
+        this.DEBUG && (this.node as any).slotOwner && console.log(indent()+`slotOwner: ${(this.node as any).slotOwner.nodeName}`);
+        this.DEBUG && (this.node as any).slotIndex && console.log(indent()+`slotIndex: ${(this.node as any).slotIndex}`);
+        this.DEBUG && (this.node as any).ownerElement && console.log(indent()+`ownerElement: ${(this.node as any).ownerElement.nodeName}`);
+        if (!this.bEndTag) this.indent += 2;
         return true;
     }
 
diff --git a/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass.html b/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass.html
index c757895d6..a16b9d51c 100644
--- a/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass.html
+++ b/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass.html
@@ -1,9 +1,9 @@
 <!DOCTYPE html>
 <html lang="en-US">
   <head>
-    <title>Issue 741</title
+    <title>Issue 741</title>
     <meta charset="UTF-8" />
-    <template id="my-list" >
+    <template id="my-list">
       <div>
         <slot id="slot1" name="heading"></slot>
       </div>
diff --git a/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass2.html b/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass2.html
index 92f128274..2daf0ce79 100644
--- a/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass2.html
+++ b/accessibility-checker-engine/test/v2/checker/accessibility/rules/aria_parent_required_ruleunit/webComponentPass2.html
@@ -54,7 +54,7 @@
     <main id="mymain">
       <h1>Test page</h1>
       <my-list id="mylist">
-        <div role="heading" aria-level="4" slot="heading" id="'mydev">Something</div>
+        <div role="heading" aria-level="4" slot="heading" id="mydev">Something</div>
         <my-list-item role="listitem" id="mylistItem">Sample item</my-list-item>
       </my-list>
     </main>