Building a Kali GNOME image

Kali experts:

I am trying to build my own GNOME image, I did so once and saw that virtualbox extensions caused it to error out and not complete. Thus, in an effort to avoid downloading all the packages again if run the build with "--no-clean" after deleting the offending package from the cache directory, will it try to redo and complete the build then (presuming no other issues become occurring)?

If I wish to add a couple of packages (and again avoid a full cleaning and downloading of packages), will the build script read the variant-gnome and add whatever packages I added to that file even if I use the "--no-clean" option?

Thanks and stay safe from thugs and healthy during this Chinese Plague.

Stuart