here is the steps
rip the files from the 2.50 data.PSAR
put the F0 and F1 files in the root of the memory stick
REMOVE the file X:F0/vsh/module/impose_plugin.prx
use umd emulater to emulate the files.
it will boot up 2.50 BUT nothing works. it hangs as soon as you try to boot something up