The game doesn't respond to controls, so you can't start the game.
Doesn't matter which version pcsx2, which plugin, and its been this way I think maybe always. Its been this way since as long as I've been trying it.
Note for tracking this game bug: It's most likely that SIF died, and with it most IOP functions.
Sorry for a bumping an old thread, but I thought I should mention this.
I just tried playing AC5 on r1888 with the most recent beta plugins. You can actually almost get to gameplay if you keep smashing the start button through the opening menus and cutscenes. It seems like if you stay anywhere for more than a few seconds (watch the opening movie, for example) everything slows to a crawl and the game stops taking user input but in the first few seconds everything works fine and you can interact with the game.
Not sure if that's helpful at all.