ff7 with 3.90m33-3

i've used 2 different rips of disc 1 and get the same problem. (both are [u] )
when i encouter the guards after jumping from the train (first fight of the game), the screen gets scrambled, and my psp turns off after a few seconds of being frozen.

is there something in the recovery menu i should change? does it just not work well on this firmware? if so, can i downgrade to earlier custom firmware?

you need to run popsloader
its a plugin that uses files from previous firmware to run PSX games

then you'll need the pops files
which if you use the search function you can find out how to get those
(they're illegal to distribute)
run it in 3.52 or 3.71 (those are the best i've seen, i personally use 3.52)