Richard Skinner and I have both tried to tackle this problem. I have also tried importing SketchUp models through Blender. In the case of SketchUp, it seems the .mat files were renamed to /*filename*/.mat.meta. I think the problem may lie here, as Blender seems to recognize the existence of the textures and their grouping structure (which faces they apply to). Both Richard Skinner and I have had more important things to work on and have not directly solved the problem, but their is another solution. Schmatzler was working on retexturing a model in this thread:
http://www.i-war2.com/forum/3d-modeling/3191-retexturing-the-dreadnaught?limitstart=0
Also, here is here Richard Skinner and I were discussing textures:
http://www.i-war2.com/forum/3d-modeling/3181-i-war-2-revamp-unity-3d?limitstart=0
This is one tough navy, boy. They don’t give you time off, even for being dead. -Clay
Storm Petrel