Error: "Broken aspect ratio and not an animation" on Client Startup

[Offertorium]

Hi there,

i have an Error on start up my priv. Modpack.

Error: http://pastebin.com/MdzVtLEd

What does this error and can it crash my Game?

My Java Version:
java version "1.8.0_60"
Java(TM) SE Runtime Environment (build 1.8.0_60-b27)
Java HotSpot(TM) 64-Bit Server VM (build 25.60-b23, mixed mode)

My OS is Windows 7

Thank you for your help and your amazing Mod

Bye