1. I&II were released as Origins on PSX, IV as Chronicles (w/Chrono Trigger), V&VI as Anthology. III was never released on the PSX as far as I know - only on Nintendo DS.

2. The awesome script changes mostly pertained to the GBA re-releases those games, I believe. As for the PSX scripts, it's been at least six years since I played those versions, so I haven't the foggiest idea.