I'm using Substance Painter, and for some reason, on this current model, I cannot paint over specific polygon faces. Initially entire sides of the model could not be painted on, but I found out this was because they were mirrored and I had their UVs displaced off the main UV space for baking purposes. So I fixed that by…
The problem came back all on it's own. Different faces this time. Once again I didn't even change the model. The color picker is uselessly inaccurate as well though, among other things, so for now I'm just done with Painter. Maybe a few versions from now it'll be worth using for hand painting textures and I'll give it…