Play Ratchet on custom firmware
Like many PSP owners, I like the added functionality of Dark_Alex's custom firmware. What I didn't like though was how Ratchet & Clank: Size Matters didn't work on my PSP because of it. Luckily, the fine folks at DCEmu have come up with a solution. Let me run you through it step by step, so you too can get Ratchet swinging his wrench on your custom firmware.
First, totally turn off your PSP (not sleep mode)
Now, hold down the right trigger and turn it back on
This will bring you to recovery menu where you can change several options
Configuration: Game folder homebrew (currently:3.XX Kernal), Use NO-UMD (currently:disabled), Fake region (currently: America), Free UMD region (currently:enabled)
Advanced configuration: Plain modules in UMD/ISO (currently:enabled)
CPU Speed: Speed in UMD/ISO (currently:266)
Plugins: All disabled
And that should do it. Now you can play the greatness that is Ratchet & Clank: Size Matters. Thanks again for the great fix DCEmu community!