Hey guys, I installed Episode 4 and have played it when it came out from start to end with no hassle.
Recently a friend of mine created a second save game and played through and reached episode 4. But rather than load it hits a black screen and just plays ambiance music, I went back to my game and checked and it's done the same thing.
I have uninstalled the local content via steam and reinstalled it twice to no avail. I have even created a new game and played it all the way through to episode 4 and reached the same result.