I'm having the same problem. I'm running GZDoom 4.14.2 on Windows 11, if it matters. I've tested it with only this mod and the patch, in the correct order. At least the pistol definitely keeps reloading.
I see what you mean, I tried it on GZDoom too and had the same result. I added some extra lines to the code and it works fine now, although it was working just dandy in Nugget without the extra lines. GZDoom is a strange beast lol