Hey PirateTony,
I did not realize you were on the UE4 Masterbranch of GitHub, which is an untested and unofficial version of the engine. The issue you are having is known and we have a process to work around it. After you have compiled the UE4 Editor in development mode, you will want to build the following with the correct scheme.
- ShaderCompilerWorker in ‘Development’
- UnrealLightmass in ‘Development’
- CrashReporterClient in ‘Shipping’
Unfortunately, there isn’t much in the way of reporting a bug as this is considered bleeding edge and we do not provide official support for unreleased versions of the engine.
Thank you,