If a CAD file is in one part and the format is IGES, can I add different colors in Keyshot?

I made the tutorial.

Answered with a tutorial: https://grabcad.com/tutorials/if-a-cad-file-is-in-one-part-and-the-format-is-iges-can-i-add-different-colors-in-keyshot

Try right clicking on the doors and choose "unlink material". If this doesn't work try editing the iges file with Inventor Fusion, or importing it in your modeling software and saving it as a part or assembly (for example slprt for solidworks). Then try importing it again in Keyshot.

I usually open such "dumb" files in SW and do a feature recognition process. That usually creates a number of bodies (when possible) and from that newly created/converted file, it's usually possible to get different faces which are recognized in Keyshot. Lately, I don't use it at all, since PV in SW is now integrated and works pretty much satisfactory for all my needs...

I usually have to make the faces I want to have different materials, different colours before I import it into Keyshot, this way it will be imported with differnt coloured faces in the places you need it and this allows you to apply differnt materials to those differently coloured faces etc.