ok so go here
Popsloader Easy Installer for 5.00 M33 v1.1 | Pops Installer, PSP Hacks - PSP Slim Hacks
download, and install! make sure it points to the root of your psps memory stick known as ms0:/
example of this is J:\ (my psp) C:\ (my computers HD) get it?
then just enable it, now on MHU i think u just relaunch the mhu installer and it loads the recovery menu, select plugins and enable.
i have summerized abit but its quite easy, just be careful what u change in the recovery, and DO NOT mess with anything flash at all! let me know how it goes plz
EDIT: to use popsloader HOLD the R trigger as u launch the game and it will bring up a list of pops versions. the original is pops version 5.03 since u have 5.03 mhu....
check here for what version u should be using
http://www.gamerspress.com/index.php...atibility_List
please not this list is note perfect and sometimes i can use 5.00 (on 5.00m33-6) pops to load alot of my games
EDIT2: yes the psx eboots go into ms0:\PSP\GAME\THEGAMESNAME\eboot.pbp but im sure u can do that since ur problem is with it crashing not getting them to appear...