@ALL: Thank you very much for comments above!

@Jetpack_Monkey: Maybe I can find the cause of the error, if you send me OBJ and MTL files which results the error with the OBJ2MDL. And MED of the 3DGS 6.314 can load MDL5 from this software. I usually convert the MDL5 to a MDL7 with MED, in order to optimize texture.

By the way, I want to post some info about making 3DGS models by working with the Poser.

I know original Poser models and most of famous 3rd party Poser models(such as the DAZ) cannot be used for 3D games(as mesh), without special permission of the author(or someone who holds certain rights).

But, several years ago, I found a great Poser model named "MAYA":
http://www.3digitalcrafts.net/studiomaya/
And, I noticed that its Term of Use about re-distribution are very friendly!
But, a problem is that the original MAYA model is very hi-poly.

So since last year, I have struggled to make good animated 3DGS human character models more easily and less costly, by working with the Poser, and using the MAYA model. For that purpose, I developed most ideas and programming codes of my "MDL reducer" and this "OBJ2MDL" tools last year. And following screenshot is a one of its outcome:

Above was created for Xmas of 2005, but wasn't published because of my busyness. She and her cloths are both from the Poser artwork of the StudioMaya above. I constructed her in the Poser with many easily added animations("poses"), then exported as multiple OBJs, converted it to the 3DGS MDL and reduced its polygon, by using my tools. Its still a bit hi-poly but moves good with my hardware.

I want to share these info in this forum, because I want to develop more good solution about this, and to share great Poser artists info like the StudioMaya.