disappearing natives???

Yeah, my WE spits this out at me when I'm trying load a map that was created with WEHelper. The map uses the casters system which has a few FirstOfGroup calls in it, and whether I try to load it in WEH, WEU or the normal WE, or whichever editor comes in the JassNewGenPackv2, I get the same problem. Reinstalling from scratch fixes most problems. Anything I should try before this?

That would basically mean you used some GUI action that is an equivalent to FirstOfGroup in Jass. I don't think an action like that exists in standard editor so try again with WEU.

FirstOfGroup is a common.j native though, and on top of that, I tried to remove all instance of FirstOfGroup from my war3map.j (via mpq editor) but I think that didn't happen. Still, it doesn't open for the same reason. Reinstallation of WC3 has made it so it opens in WEU, but still not anything else. Any other ideas?

Did try to replaced common.j with an imported one?
If yes, remove it and try again, because i tried to add the natives for Getting the gold and wood costs of units but then WE told me, that the entire map trigger is wrong.

Not that anyone was losing sleep over it, but WE just up and fixed itself. Tried one time and it didn't work, then the next time it did. Computers are such a love-hate relationship.