Ok, Jugg3rV, If you have minechem items in your hand if you shift right click on certain things, like ender IO tanks, or fusion or fission chambers you will crash to desktop every time, at least on a Mac. The other problems I can't help you with.
Thx for replying, but i didn't shift click with the minechem items.
I cannot even replicate the problem. It just happens. But at times i think, it has to do with NEI and the recipes.
When the problem occours i cannot access certain inventories, mostly vanilla chests, barrels and functional blocks. The strange thing is, that some inventories can be accessed.
Most functional blocks froze, as if the game won't generate ticks anymore. Still i can move, open doors and such.
When closing minecraft by save & exit the server shutdown screen will not finish closing MC and the process has to be removed by the taskmanager.