MoI V4 beta Feb-9-2018 / Mac OS X Yosemite V 10.10.5

Hello Michael,
it seems to be something wrong when exporting with the OBJ format.

I have an open cube here (fig. 1).

In OBJ format, in Keyshot it is displayed as a closed body. (fig. 2) - not correct
In FBX format, it is displayed as an open cube. (image 3) - correct

The same applies to this construction (fig. 4) in OBJ format (fig. 5) - not correct

Can you check that, please?

Thanks in advance

- moritz