From what I've read, I agree that ??da files seem to be like .a files for the field sprites, but I thought .fda was part of the Field files, not World map, and the Field has quite a bit of animation that I don't think has been entirely figured out yet. I don't know if this is just a bug I've encountered, or a general problem, but None of the tools seem to display any of th backgrounds that had animation in them (ie, the Highwind's cockpit and Deck with the ground rushing under it). Like I keep saying, I'm just throwing out oddball ideas in the unlikely event I might stumble across something usefull.
Speaking of, I haven't said anything about it before, because I don't want to come off as a complaining ingrate, or whatnot, but about half of the programs that I've downloaded from the various sites don't work (Namely Gast, Ultima, Jenova, Jenova-Birth).. And yes, I've downloaded the various libraries, DLLs etc...several times, and tried just about everything I could think of to remedy the problem myself.
Also, there are a bunch of sprites in Char.LGP that Ifalna won't show, but I'm not sure if that's a general limitation, or a problem on my end. If the former, apologies if it sounds like I'm complaining; I seriously don't want to seem that way. If these problems aren't something wrong on my end, then maybe there's some way I could be useful, at least by providing infromation on what's going wrong, or whatnot.