So... that thing I was worried would happen... happened. After several plays on the Jan 4th build, it has suddenly refused to render ambient lighting. I managed to get one play on the next build (Jan 8th) but it lost lighting the next time I loaded up the build. The next one, Jan. 12th, gave me no lighting from the get-go, so I decided to load up the March 7th build again and noticed that I had a radar again. It would seem however, that this is due to my adding radar icons for every ship. It would appear that the default dots aren't rendered in this build. I also noted that grid lines in the briefing screen are missing, as well as subsystem targeting brackets in the target window aren't displayed, as well as the bank-identifier lines in the loadout screen. I also found that lighting is ONLY being rendered from suns. A ship will appear completely lit on the sun-side, but completely dark on the other. I'll try a few later builds and see if there are some other interesting differences.