I have absolutely NO idea what's going on there. But I'd start by using lit spheres. Right now you have unlit spheres (ones which just display color and don't respond to lights). Try adding material to the spheres which make them lit, and adding some light, and see if you see something.
> I've run into some problems with the underlying Java3D in MASON. I've managed to get things working by using the latest 1.6.0 Java3D release, but only on macOS. On Windows the sphere's do not appear to be rendering correctly. I've laid out the problem better on Stack Overflow in the following question - http://stackoverflow.com/questions/42054250 - however, this is a bit of a niche question.
> Has anyone on the LISTSERV encountered this same issue? How were you able to resolve it?