So I think I found a bug with the sneaky block. If I place the sneaky block down and the right click with carpet it and then try to remove the carpet it crashes the game. I tried it is single player creative then turned it survival and it crashed there too.

Hello, I need the full crash log to know what is actually going on. A crash log is always generated. You can find it here profile folder/logs/fml-client-latest.log

2017-05-24-1.log.gz

2017-05-24-1.log.gz

The log you sent is the server log. I need the client log.

Just did it in single player here is the log
First Player Crash.txt

Okay, this issue was fixed some time ago and is a duplicate of #55 Please update to the latest version which you can find here