I tried
everything, and they still don't work
Installation is very simple, so it's impossible that I messed up (as I previously said, SL1982's or YarLson's field enhancements work perfectly, as all of Avalanche's menu graphics, and I put your battle folder in the same folder as the field one).
Magochocobo's corel reactor works though, since it modifies the LGP archive itself. Maybe it's a problem with Aali's 0.7.8b driver ? (because of my ATI card, I can't use 0.7.9b *battles don't load* - or 0.7.10b *battle textures messed up*).
It might be selfish, but would it be possible to transform your PNGs into lgp files (like Magochocobo's rjaa, rjac, etc.) ?... ...I'm almost sure you can't do that, but I figured there's no harm done by asking ^^