Hi Nico, can you show an example of your problem with n-gons?

For just rendering n-gons should work fine, there isn't any benefit to having "all quads" if you are only rendering. It's when you are applying subdivision surface smoothing that all quads is needed. But typically it does not make sense to apply subdivision smoothing to a CAD model.

The MoI v3 Mac version uses a mechanism called "Wineskin" and it has various problems. For version 4 I've done a major rewrite so that the MoI mac version is a native compile and doesn't use Wineskin anymore. So that's why there can be differences between those versions.

When you say you can't launch v3, what happens exactly like is there an error message that is displayed?

- Michael