Regarding folder sorting on Windows: I think I got it
! The damn model only sorts items below its "root path" and I was using QDir::rootPath() as the starting point which is "/" on Linux / UNIX / Mac OS X, but on Windows it's the system drive's root directory (i.e. "c:\"). Effectively, only "c:\" and its sub-folders were sorted...
Now I'm using "QFileSystemModel::myComputer()" as the model's root and as a result everything
is sorted as expected (at least here)