The fix is to not use PSPI Rod. Take PSPI out, and set the path for the guf files and all is well. Indeed, if you don't set the path to the guf files, you can now do so in User Filter itself and all is well. That's the bug. PSPI vs. User Filter. If you have PSPI before user filter, the path to the user filter will magically get replaced with a blank line and PSPI, of course, will work. Vice versa for User Filter. Michael said he fixed this issue, but I guess I have to wait for an official release, but maybe it already got released to git (did I say that right) so you can build GIMP from the new files and see if that fixes this issue for 32-bit GIMP.
