Just a thought occured to me now. Does UDK engine support the latest steam sdk? I am talking about my custom build of UDK, which is based on May 2011. I am using the latest steam sdk version, and I can’t do different, I am not going to use an outdated version of the steam sdk since it updates itself automatically and I need to ensure that my game runs smoothly on the steam client.
So maybe that’s the problem? My UDK build is not compatible with the latest steamworks?
I have seen this happens with UE4: