@farquhar So I'm assuming you're talking about grouping different voxels all in one mesh? Well if you are then I suggest using the "split-off" tool, in the modify tab on the menu/HUD. It will, do exactly what I think you're talking about, so select the voxels in then click that button and it will make another mesh in the same position/location with those voxels. It separates those voxels from the original mesh, as the name suggests.
You can learn more about it here: http://minddesk.com/learn/article.php?id=92
I suggest also reading everything in the "Learn" database, like read everything (it won't take that long). You can find the main database here: http://www.minddesk.com/learn/
If you have any other problems, that cant be resolved by reading the "Learn" database or cant be solved on this forum, then I suggest contacting the developer here: http://www.minddesk.com/contact.php
Good luck! I hope I helped: slight_smile: