i gonna check that, you think is because of the Atrac thing?, but i noticed that rev 2954 doesn't work even with media engine disabled 
Im talking about the boss with claws and circle glasses, the first boss (clown(buggy)) worked disabling "Media engine" this boss not.
should i upload the savegame?, you still need to fight the boss to advance.
Edit: Ok i tested rev 2827 and doesn't work with media engine enabled
Edit2: Ok this is strange, i tested again with rev 2954 with media engine disabled and this time worked, im confused, it first slowed down the menu for a second, and then it worked.
Edit3: i think i got it, when the "you win" screen have multiple pages jpcsp slows down
Edit4: Yep, i have just noticed that the boss on the screenshot on the first page i passed without any problem with media engine enabled. Is not simple as disable media engine to make this game work.
Im talking about the boss with claws and circle glasses, the first boss (clown(buggy)) worked disabling "Media engine" this boss not.
should i upload the savegame?, you still need to fight the boss to advance.
Edit: Ok i tested rev 2827 and doesn't work with media engine enabled
Edit2: Ok this is strange, i tested again with rev 2954 with media engine disabled and this time worked, im confused, it first slowed down the menu for a second, and then it worked.
Edit3: i think i got it, when the "you win" screen have multiple pages jpcsp slows down
Edit4: Yep, i have just noticed that the boss on the screenshot on the first page i passed without any problem with media engine enabled. Is not simple as disable media engine to make this game work.