This is a simple NO UMD FiX by Reborn:

1) Extract Megaman_Powered_Up_USA_PSP-DMU to a folder on your PC using iSOBuster or similar utility.

2) From your original PSP_GAME folder move all .PNG, .SFO, and .AT3 files to the MEGAMANU folder from this pack.

3) Next, from your original PSP_GAME folder move the USRDIR folder to the MEGAMANU folder from this pack.

4) Now follow the instructions as normal from the included NFO file:

Put the 3 folders to memstick and start runumd ....

Now boot using RunUMD.

NOTE: Although this is labeled a "NO UMD" release, that just means you don't need the actual MPU UMD in the drive to play the game, however, you will need a UMD in the drive to run it (any UMD game should work).