• Where is game save data stored?
• What about the log?
• What's the difference between Qt and SDL builds?
• I have questions or need technical support. Where should I go?

They are stored in user/savedata/1/<Game ID>

For now, only the last log is saved.
It's located on user > log > shad_log.txt

• Qt Builds: Qt builds have a GUI and it makes configuration easy.
• SDL Builds: SDL builds contain only the bare application to run the games and make them work.

You can, but we don't think it will necessarily improve performance.
To do it: Win+G, go to Settings, check remember as a game

You can go to the official shadPS4 Discord server. There are kind people there who will be there to help you!