Nothing gets written to the registry. The program just reads from a file and changes key strings and variables within the program itself (and only that program). I don't have an installer either as I don't have any nor have any real need for one, maybe just for creating shortcuts.
"You level up the fastest and easiest if you do things at your own level and no higher or lower" - useful tip
My 2D game - release on Jun 13th; My tutorials
