Hi!
Now I have copy of Workbench 1.3.2 (What Mrs. Beanbag recommended to me). Workbench doesn't have any graphical errors. I think that it would be region problem, because I don't know what region insanity fight is, but I do know that Workbench is region free, so you can use same Workbench on NTSC or on PAL system. My Amiga 500 is PAL.
Thanks -Eemil