There was one thing I was wondering: is the story in the demo (how Tyber acquired the holocron and how he got sent to Kessel) a part of the main game? Or to be more specific, is this a mission in the game itself or is it a "prequel story" that explains the background? I'm only asking because I was under the impression that the game would start with Tyber's escape from prison.

One of the Devs would probably answer this better.. But i will give it my best shot.

I think it's Part of the main game.. Why? He got sent to the Kessel space mines because of Jabba .. Because jabba thought he became too big.. and Could pose a threat. However Tyber knew things about the imperials ( Contacs , and Personal experience) So i think the Holocron will probably function as a Power Up device for the Eclipse ( This is highly Suspected )

I think its only a prequel

Its probably going to be a prequel to the real story, but it may end up in a tutorial for the full game.

Yes, as a tutorial it would make sense.

I just thought it was pretty cool to make the demo a stand-alone thing, instead of just a cut-out piece of the main game. And you also can squeeze in a little more story that way.

The demo leads into the main game. =)

That's cool. I thought that at first, but it's good to hear from the horses mouth.