Hello realesthete,
I’m glad to hear that you were able to fix your problem.
As for the build times, please note that it says that it takes 10 to 40 minutes, 10 being a machine that is made specifically for compiling builds. Source builds, depending on if it is a fresh build and if only a few changes have been made, can end up taking quite a while.
We currently don’t have any plans to fully integrate Gameworks and SpeedTree into the base engine, as they are optional features that aren’t needed by all developers.
While it doesn’t allow for custom integration, we do have a fully built version of the engine that can be downloaded through the Epic Games Launcher.