Your comments

Fixed in 2.9.1, please update and let me know if something is not working as expected.

We fixed the Quit issue recently. I'm closing this for now. Let me know if you can reproduce the no-extension problem.

We set the default materials to "standard white plastic" for imported OBJ files without materials in version 5. Give it a try there and let me know if you need anything else.

We added CPU cores selector to the settings window in the latest Boxshot 5 beta. Give it a try and let me know if it helps.

I believe it's been done in Origami and then imported to Boxshot for rendering. However, you can achieve a similar result by using a number of Extrude shapes combined together. It lets you make triangle panels and even the top one with holes.

They are usually of a different shape, so I wonder what exactly types of display units can be done this way? Maybe you have images?

We have this in plans for one of the next update, but so far the metadata approach is the only way.

It would be nice if you can point to the implementation you want to match.

I guess the question was about Owlet, so I moved the topic to a proper forum. Correct me if I am wrong.

At the moment there is no easy way to quickly import multiple STL files into a single scene. Owlet supports many other formats, maybe you can export the whole scene to Collada or FBX?