All of the .ini files are now .tbs files, and I have no idea why a readme would be stored in appdata. But it sounds like the same issue, so wiping your configs (if you can find them) should help.
FWIW, when it comes to finding specific files on Windows I use a program called "everything", I forget where I downloaded it from but it does a lot better of a job searching for files than the Window's search bar does.