Can't start any UE4 games

I recently downloaded the games RIftCoasterHD and Subsea Experience. Both run on UE4, and both won’t start. The games came in a ZIP package, so there was no setup. When i try to start them, in the task manager a process appears for short time and then disappeards again.

I tried:
-Running as admin
-Updating DirectX (June 2010)
-Updating C++ Redist 2013
-Updating .NET
-Restarting and stuff like that

Couldn’t find any solution yet.

My PC:
CPU: i7-4770K
GPU: GTX 780
RAM: 16 GB

Thanks in advance.

Mfg FlomoN

And Windows 7 SP1

you got any logs?

this looks like a log, but it doesnt change after every start:

except for this i found the same file for the riftcoaster, but i think, this has something to do with the creator of the game.

Anyone found a solution to this problem? I have the same issue and aI’m trying to find a solution to it for a few days now and it’s killing me.