0.8.3 Experimental Files for the Expanded Galaxy Project now feature demo levels of the Endar Spire.
The video is outdated and the levels are now 99% functional / can be played through, I suggest starting a new game, skipping the prologue and then warping to "end_m01aa"
In the future I might work on more levels, I found deconstructing and rebuilding these levels to be a really fun experience.
I also think that they play and feel a lot better.