- From the 3D window use Save as a 3DS.
Check Save by Materials as an option.
- In SU when importing check the options for 3DS and select merge coplanar faces.
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If the model is too big you can export from AC smaller pieces of the model and as long as you don't move the model in SU they will import in the correct place.
BTW why are you importing to SU, there is not much you can do in SU that you can't do in AC and AC is more efficient with big models.
Eduardo Rolón AIA NCARB
AC27 US/INT -> AC08Macbook Pro M1 Max 64GB ram, OS X 10.XX latest
another Moderator