Unfortunately, none of the things in this log have anything to do with HammUEr, so I can't really help you with this.
Some of those dll errors seem to refer to intel vtune, but a quick google doesn't seem to give any decent solutions, apart from maybe needing administrative rights when you install/run unreal engine?
Good luck, hope you figure it out.
I had just recently found out about this plugin for UE4, and I am actually running into the exact same issue. I am able to get the textures imported just fine, but when attempting to import .map or files it finishes loading from master list, the I get an immediate CTD.
I did try loading a .vmf which I had exported from Hammer Source SDK (originally on GoldSrc, used converter) and the map loaded into UE4 only once, any other time (same map) nothing showed up after loading and referring to master material list.
I'm running Epic Games Launcher as Admin, and I get the same thing as brikkew. I'm on UE4 4.19.2 w/ latest build of HammUEr