Some final code requests (and screenshots)

You won't get far with FF3usME changes unless you know what you are doing or are a bit lucky. Those three words in the animation data are simply pointers to BG1, BG3 and sprite animation scripts in bank $D0 (disassembly here). If you just change numbers, you are pointing to the middle of another script and this will never do anything good as result. If you put the value(s) of another spell, make sure you replace a BG1 pointer by another BG1 pointer as an example. You can't have two sprite or BG3 scripts I think in the same animation but I've never tested this.

Some spells only have one or two scripts. To find a good mix you gotta swap values logically. The disassembly can help to identify scripts pointers which will always be the beginning of a script.