You can't run ANY emulator/homebrew on PSP 2.50 without a UMD of GTA: Liberty Cities. There is an exploit on that game that lets you run un-official code (Such as emulators) on a PSP 2.50. So if you don't have GTA, then you can't play any homebrew. And no, you can't go back to the old software (PSP 1.50) if you were wondering...So your choices are the following:
1) Stay with v2.50 and only play official Sony UMDs, music & videos.
2) Stay with v2.50 and buy GTA so you can use emulators & homebrew.
3) Upgrade to v2.71 and never play homebrew again. (If you do this, you're officially an idiot)
Also, every SNES rom works on PSP (Using snes9xTYL 0.4.2)
Download snes9xTYL 0.4.2 from the official site,
HERE
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