One of the earliest versions available out there for this game, it contains SH as Sonic and BS as Dark. Strangely enough, Dark's BS ACTUALLY uses Rose's level design, or an early version you can see in the final game through memory editing as Team Sonic and Team Chaotix. The ending is also at the same spot as Rose's. Through testing, it seems that it that of team Rose, seeing as the cannon past the Goal Ring isn't even there.
The Goal Ring sound is basically the same one used in Sonic Unleashed... Pretty cool!
Very similar to the 10.8 Prototype, only a very stripped down, days if not hours later release regarding the build branch from which this 'UST build' is split from. Nothing more should be said, as the bulk of it will be below.
Chronologically, when was this released?Edit
Before the game was even finished from a level standpoint, considering the physics and camera are the same than the Prototype 10.8, which was after all of the levels were complete. This demo has byte for byte identical menus (unused) to that of the 10.8 prototype, except that the audio menu got translated to Japanese. The Goal Ring sound is very interesting, as it wasn't even used until Sonic Unleashed, a game that came out years later. This isn't present in any of the other versions. Currently, little knowledge and hacking has been done, so until we know more... nothing more can be added here.