Interesting idea, but virtual isn't going to work on the system with 10.9 because it is running OSX Server, and 10.9 therefore has to be the root OS. There's no upgrading this system and then hosting a VM downward, and then there's no upgrading the system in general since Apple deprecated Server starting with 10.10.
Frankly, I'm mostly just annoyed with Chitubox' web page alleging 10.6 operability and getting the no-can-do dialog about 10.11 after downloading.
Mainly interested in Chitubox for this particular CPU because the server is the only Mac in the building where the Photon lives, the Photon being something you really don't want in your home office. Was just hoping to streamline ops instead of sneakernet between isolated systems in two different places. Probably the better bet is seeing what it takes to port Chitubox to Raspbian and dedicate a Raspberry Pi to slicer duty.