Metal Gear Solid Portable Ops

[Zero8000]

I have a problem. Yesterday I got MGS-PO from my friend. I checked the file and it's name was: Metal Gear Solid - Portable Ops.cso. When I try to play it, it won't work. I mean: upon loading it to PPSSPP, it stays black for a second and says that PPSSPP has stopped working, and the emulator closes. Could somebody help me with that?

Edit: I forgot telling you. It's the NTSC version (ULES). I tried with the PAL (ULUS) version, and it works perfectly. The problem is a matter of taste: I don't like PAL versions. Prefer NTSC.