[Tool] How do I fix PokemonGameEditor?

Hello, I've never ROM hacked before and I was just making one for my friends and I. Whenever I try to modify a Pokemon or something it just gives me and error and lets me do nothing. I was really looking forward to making a ROM hack, but I don't know what to do. Does anybody know what I need to do? I reinstalled it 3 times, all different versions.

What ROM base are you using? Any time I had similar issues, the ROM base was either corrupt or not supported by PGE.

First try Advanced Offset here: https://www.pokecommunity.com/showthread.php?t=347441
If it's a problem with a specific Pokemon, I recommend using Gen3Tools (G3T) for said Pokemon.