Hi Mike, when you exported the OBJ file what setting did you use for the "Output" option, this one here:




If that is set to "Output: N-gons", then that's probably what's causing your problems, if you change it to "Output: Quads & Triangles" instead that may solve your problem.

If .3ds works good enough for you and gets the job done then well certainly use it - but also with .3ds it will be easier to run into some shading quality problems with it as well.

- Michael