I'll quickly summarize my ultimate goal: Replacing % to force target to fight for you mods with %chance to cast Fireball.
There's no issue with figuring out how to replace the suffix with something different. (Rather than worrying about casting the Fireball, I'm just using a +crit chance modifier for now.) It's pretty straightforward, although Steam-related editor issues can kind of cause problems. (Like when it tries to load multiple versions of the same mod, which it seemed to try to do.)
However, changing the affix like this only affects newly spawned items. So, for instance, Sulaman's Valiant spawns with 1% chance to turn enemy to your side for 60 seconds. If I replace this with, say, +2 crit, then spawning another Sulaman's Valiant gives me a SV with +2 crit...but any Sulaman's Valiants already on my characters retain the 1% conversion chance.
A large part of the reason I'm interested in this is that the stat has been kind of a nuisance on the items I'm already using, and I don't want to have to respawn the items (particularly since one is already enchanted) in order to do the conversion, since that seems a pretty extreme solution.
The only other option I can think of, though, is to modify the actual effect directly, which seems to be tied into Charm skills that I don't want to inadvertently break. (Or to duplicate the effect, point the Charm skills to the original, then modify the actual effect, which seems likely to result in my forgetting things, or breaking characters who already have Charm skills learned.)
Does anyone have any advice on how to handle this?