Virtuous Flame, aka Liquidzigong, has released PopsLoader for Custom Firmware 6.xx PRO. PopsLoader is a better means to emulating PSOne (PS1) games on the PSP; rip whatever game yourself, ISO it up, and play on.
PopsLoader does however take some preparation — you’ll be required to dump & decrypt select firmware files yourself. Everything needed can be found below — check README.txt (included) to see exactly what’s up.
You can find the PopsLoader source code and other updates over at the project homepage
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