Parts of object. going black - help!

[default02xcyv14wrg1]

Hi, Im a beginner with Adobe Dimension. I am applying decals to a cube box, and when I render the image, the bottoms of the product turn black (see images).
Can anyone help?

[Ussnorway]

I'd say your Mac is struggling to rendor but you can test that pretty easy... Share the Dn file with someone on a Windows system and see if they get better results