Hm... I've never seen this error before. Did you accidentally assign more materials to the regular model than you did with the LOD? But even then it shouldn't give an error. I'm not 100% sure what's wrong.

I didnt assign anymore materials to any of the LODs. is this something im doing wrong or the game?

Well I haven't heard anyone else having this issue, so it seems like something on your end. Are you using photoshop or gimp to make your textures? In the meantime, you can try reassigning all your materials from within blender.

photoshop, ill try that, thanks

I figured out what went wrong, i accidentally inserted a face that didn't have a material assigned when making the LODs.

Thank you

Ah, glad you figured it out.