How said. Maybe the Games aren't compatibel with the Spoofer.
What MM version are you on?
I figured out that some games have to be played on the internal.
My most common error at the moment is that Rogero 4.30 sometimes has problems reading discs.
To fix this I have to go on MM, press on "Load disc" Which is an infinite loading time (since it can't read the disc) then turn off the ps3 from the back. Just to get it to read the disc again.