well, ingame it looks like this:


when it should look like this:

did you freeze the UVs and the model before exporting?

yes,I freeze everyting before i export. I retextured it and ended up with this:

Here are a couple of tricks to try.
After doing the Freeze (not FreezeM) also do a freeze all transforms.

If that doesn't work try this:
If it is all one model select all the polygons and under Model/Create you should see a Extract Polygons (Delete) that will create a new model mesh and just leave the name of the old one, you can delete that. Then rename the mesh to what ever makes sense to you drag it back under the dummyroot and try exporting. Oh your texure job will be retained using this method so you don't have to do it over again.