MINECRAFT: Mo Creatures arent spawning, why?

I installed Mo Creatures correctly but not all mobs spawn. I've been playing for hours in different worlds and the only mobs that spawn are bunnies, chickens, goats and birds in some worlds. And in some worlds hostile mobs spawn but in others only vanilla hostile mobs spawn. I found raw fish on the floor and i assumed an animal killed a fish or something but then i saw a dolphin in land dying and it gave me fish and i saw a shark in a tree dying. It seems they are spawning in random places and there's no water mobs except squid. I go to Mod options and it says "Test 1 test 2 DISABLED" and i thats it. And on the main menu i go to "Mods" and Mo'Creatures doesn't have the config option, only the disable option. Why? What's going on?
What can i do?