Hey,
first of all: AWESOME WORK!! I always wanted to rebuild a CS GO map in UE4, just to see whats possible, but this makes everything so much simpler! Except that I can’t get it to work 
I tried using the steps shown in the HL2 Ravenholm demonstration, but that doesnt work for me at all. When I open the .vmf file with the settings from the demo video (as close as they get since there are more settings now), width and height of all meshes are set to 512, ND is ticked for some of them (I’m a total noob regarding hammer, so I dont even know what that means) and there are no materials assigned whatsoever.
After looking through the thread for an anwser, I think I didnt find one, so hopefully someone can guide me in the right direction. If you need any information, let me know!