FTB Launcher crashing with Mo' Creatures

[HowdyHowdy]

I've just tried installing Direwolf20's mod pack with Mo' Creatures added (which I have done successfully before) and now I'm getting crashes on launch, I'm following a guide from when I did it before which was around February so I'm guessing the updates have outdated it.

Here is the crash log

Looks like something to do with forge communicating with Mo' Creatures, is this a case of just adding the latest forge to the pack? I'm inexperienced with these mod packs so I've no idea really. Any help really appreciated.

 

[lavarthan]

Ensure that you have all the required files that Mo' Creatures needs like GUI Api and Custom Mob Spawner. Links to each of these can be found in the downloads part of the Mo' Creatures minecraftforums page. Follow each link and install both of the required mods by following the install guide for each mod.