I installed Zorin OS Lite desktop in Zorin 16 Core for trying it out.
I did that using the synaptic package manager.
Everything went fine. and I could get into Zorin Lite desktop. However, I see only 2 layouts in Zorin Appearance. I can see all the layouts in Zorin Core (GNOME) desktop.
Screenshot:
It was the dev's decision, you will have to ask them. But one thing I know for sure, the dev's do want you to get something for supporting them. So you not only get extra layouts, but you also get more wallpapers, as well as installation support.