Your UVs are good. Have you unwrapped channel 1 as well? In case that confused you. The channel 1 is for you textures. The channel 2 is for the lightmap. I am guessing you got that, but just to be sure. Just make sure to collapse the mesh before export you should be good. But actually, as I am looking at your image. I dont think there’s anything wrong with it. Its just that you don’t have any lights in the scene. I think thats your issue at this stage, so move on to experiment a little with lights and see what that gets you.