humm, make sure you are putting the files with the 514kb size in there,
i tried just picking out a couple i wanted upgraded, and then loaded up ff7,
and the weapons were white.
when i put in those extra files (rtae, rtaf, rtag, rtah, rtai) all the textures worked. :)
so you cant forget those, you absolutely have to extract all files, and create a new lgp.