I know it might become painful, but can you try removing Mods one by one until it works with the latest GT6? Try the Mods I do not have Compat for, first. 
Also I would need fml-client-latest.log and not latest.log
I know it might become painful, but can you try removing Mods one by one until it works with the latest GT6? Try the Mods I do not have Compat for, first. 
Also I would need fml-client-latest.log and not latest.log