A: You can find a tutorial for setting up both the game and mods here. Alternatively, opening the decompilation without any game assets present will generate a TXT file containing a brief guide to setting them up.
A: Long story short, it's to minimize piracy and ensure an extra layer of legal protection for Sonic Mania Plus and Sonic Origins Plus. Giving players paid content for free is not the goal of this project.
A: Buttons like Leaderboards & Achievements require code to be added to support online functionality & menus (though they are still saved in the Udata.bin file), and other buttons like the Controls button in the Blit versions or the Privacy button in the mobile version have no scripts and are instead hardcoded. I just didn't feel like going through the effort to decompile all that, since it's not really worth it.
A: Try turning on VSync in settings.ini.
A: A likely reason for this is that you put the decomp in a directory that's managed by OneDrive (Desktop, Downloads, etc). These directories are known to cause issues, so move your decomp installation elsewhere, such as the root of the C drive or another drive. If it's still not working, try redownloading and reinstalling the decomp.
A: Submit an issue in the issues tab and we might fix it in the master branch. Don't expect any major future releases, however.
A: This is a known issue that is caused by the scripts from this version of the game. You can either use a mod that modifies TitleCards/R[X]_TitleCard.txt to fix it, or simply set the screenWidth option in settings.ini to 400 to match the intended value used in the original release.
A: Similar to above, this is a script issue. You can fix it via a mod or by changing the screen width.
A: This is a known script issue with most Sega Forever versions of the game. Using the decompiled scripts should fix it.
A: This happens when using the Software Renderer, you can fix this by setting HardwareRenderer in settings.ini to true.
A: The decompilation only supports the OGV video files from the Blit/Steam versions of the game.
A: The RSDK file from Sonic Origins is encrypted in the RSDKv5 datapack format, not the RSDKv3 format. Repacking the files in the correct format or using Data Folder Mode will fix the issue.
A: Sonic Origins doesn't have any music or sound effects contained in the game's data file, instead storing and handling all in-game audio itself through Hedgehog Engine 2. You can fix this by simply inserting the audio files from another version of the game. Sound effects added in Origins will have to be inserted manually.
A: By default, the game mode is set to Classic Mode, which disables the Drop Dash. The only way to change this is through a mod, either by changing the default value of the game.playMode global variable in GameConfig.bin or by setting the variable to another value via scripts.
A: Sonic Team implemented Knuckles and Amy in a way where they aren't playable on the decomp out of the box. This can be fixed via mods. Do not ask about this in an issue, as we will not be able to help you. There are also checks implemented in the engine to prevent playing as these characters on release builds and autobuilds.
A: I already have! You can find it here.
A: I already have! You can find the source code for Sonic Mania here and RSDKv5 which is used to run it here.