i added the obj file type- but you should zip them- really.

one of the big advantages of obj files - is that they are text files - and they have a small number of features- so its not totally impossible to look at them a see incorrect things.

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3d models are tough -

if you use maya and modo - - they do the right thing - most of the time.

i use maya, formz, cinema4d, concepts 3d -i tried modo. i can just make models work.
I have been able to get proper texture maps and uv coordinates out of cinema 4d - with non-mangled vertices -
I also sometimes have to resort to windows based 3d file translation programs.


but it sometimes takes lot of wrangling to make 3d - even transfering files from one 3d program to another, can be traumatic and difficult.