It's a solidly crafted mesh but a bit high on the polygons for that detail level. I'd consider publishing it on the exchange if it had some textures. Nice work mate.
I think it's like Maya's UV Sets. Same polygons represented, but in another UV layout that is optimized for storing lighting information for this specific purpose.
check exporting the OBJ with polygons and not quads or triangles. Also make a copy of your object and convert that one to a mesh before exporting, see if it helps.