Thanks for reacting so fast, I just had the same problem with gb64_xboxrename crashing all the time.
However I just downloaded the new version, but it still doesn't seem to work. It doesn't crash anymore but after about 30 seconds it just stops doing anything without creating the "CONVERTGIF.BAT" file.
I think I did everything correct, first I choose the games.dat file (the one from the gamebase_v3_dats.zip file), I click on "Start Renaming", choose a picture from the Windows picture-set (a gif-file), and during the next step, I move into an empty directory, type a few letters and OK. Now gb64_xboxrename seems to be doing something but only for about 30 seconds. No "CONVERTGIF.BAT" was created next to the games.dat file

Is this another bug or am I doing something wrong?