Been there, done that (many, many times) .  It's a pain, but it's the best way to learn (doing it).

On the documentation... keep in mind that I've been messing with .obj files for 20 (?) years now, so I might gloss over something that I take for granted.  If you have questions, let me know. 

Cinema4D Plugins (Home of Riptide, Riptide Pro, Undertow, Morph Mill, KyamaSlide and I/Ogre plugins) Poser products Freelance Modelling, Poser Rigging, UV-mapping work for hire.