What OS are you guys running?
Nvm, saw it in the log.
I'm looking into the error more. Sorry about the problem.
To fix your worlds, either remove Meteor Mod and Load your World, or you may need to give the mod pack HIGH priority in the task manager. (Google How to) This might give it the power it needs to overcome it, thats just an idea tho. I will see what the problem with it is, can i get one of you to send me your forge log located in the root of the NWMP install. Should be named ForgeLog-Client-X(x being a number)
Not sure if either of these are what you're looking for:
http://pastebin.com/3mXkP3gv
and
Part 1: http://pastebin.com/awyr4wgX
Part 2: http://pastebin.com/BG4i2y8V