I am trying to find time to complete Galaxium but wanted to give you my observations so far.
I too, encountered the crashing issue with the right mouse and the first moon. I usually use that right button to select a single seedling for scouting, and after that and two more later crashes, I was afraid to touch it for fear of losing all of my hard-earned progress again. Unfortunately I can't seem to replicate it at will, and haven't detected a pattern as to it's cause.
The general layout with the layered orbiting bodies and the massive scale is quite interesting. It really gives one the feeling of looking over a massive solar system. However, after a while it becomes somewhat tedious scrolling in and out constantly to adjust the zoom so that I can accurately select seedlings and the smaller moons, and also see what is happening on the grander scale. That is a minor issue, though.
Personally, I dislike the brighter background colors. It is hard to look at and makes it difficult to see the action. Fortunately that only occurs sporadically.
So far I'm enjoying it, but haven't seen an opportunity to use the Rally System yet. It looks like it's going to be a long one, but a good one!!!