I couldn't get this game working on PSP when I converted it to an EBOOT.PBP
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Hi! Yes, it won't work on PSP, and I couldn't get it to work as well.
The reason for that is that most games from the PS1 era used an SDK that was full of bad practices when it comes to writing to memory-mapped structures. The SDK I'm using does most of it as it should be, but old emulators don't implement the accurate memory mapping features in the right way (mostly because it was not necessary). So PSP's emulator, which is very old, cannot run this game.
You'll get similar bugs when running this game on any version of ePSXe or older versions of PCSX-ReARMed: music and sound effects simply won't play.