I gotta say thanks a lot for this tool! Once you get used to the UI it's frigging awesome. Everything about modeling for source what once was tedious work with the command line tools and whatever the fuck you had to deal with before. You pretty much forget how shitty it was before since once you get ...
You need to make an alpha channel to your diffuse to tell source what parts of the texture you want to illuminate.
Any decent image software can edit alpha channels.
To me it looks like if the model is in the same smoothing group and you get errors, then those parts which are making errors have different vertex normals.
So my suggestion would be that do "Edit Normals" modifier, select everything and hit reset and then do a xform reset.
Yeah that is the same thing but as what Hollow said, in UE4 since it has the material system. Instead of using a diffuse for your brick wall to represent red bricks and the grey cement filling. You just make instances for a red brick and grey cement filling, and just make a mask of a brick wall ...
Not a easy task since you'd have to make a big ass modeled 3d skybox as the stadium but the field itself would be pretty easy to make. Go for it fellas!
@plagueofburia I think it looks pretty nice, though I'd remove the longer unused spikes unless they are going to be connected into something. That pipe texture could also need some refining. I'd probably use a color somewhere from white/gray which would fit better to the combine color space + add ...