Yeah, the video shows probably all the eye candy there will be, without explaining the gameplay at all. But then, the introductory paragraph tells you all about that.
The video also hints that it'll use all the unrealistic but fun space combat tropes.
(I understand that this thread doubles up as the new "realistic space combat thread"?)
I'm sorry but I have to say that boarding is just silly, even from today's perspective.(but it's still cool, of course)
Imagine a real world carrier, packed with tactical nuclear missiles and planes, plus a small screen of destroyers. There's just no viable way of boarding it. And there is hardly any reason to - important documents can be destroyed by the crew(in the disabled/damaged ship being boarded scenario), and usually the commander can scuttle his ship anyway. Should you manage to capture this carrier against all odds, what would you do with it? It was built with a completely different technology than your carriers, meaning, you'd have to erect an entire factory to manufacture and repair every one of the gazzilion parts that it's made of. Using it up for resources is not worth the hassle of towing it back to port and dismantling either. It's so much cheaper to just use the raw resources that your industry provides.
In the case of space combat, it's still the same, only on a larger scale.
Some effects of special relativity are relative to the speed of light, not to two observers. Remember that even satellites in orbit suffer from these effects and they are at a very small speed compared to light...
So if it's a chase or an encounter, they will be most likely moving fast enough to suffer quite a bit of relativistic effects to one another. Most likely lorentz alone, which was a pain in the ass when I was in college, would keep you from telling for sure where the ship was, specially if it was doing random motions.
The satellites suffer(or rather suffer less) from the gravity well's influence. Time flows slower near massive objects, as proposed in general relativity. It's got nothing to do with the orbital speed and lorentz transformations of special relativity.
Lorentz equations are actually very precise, there's no uncertainity in them. All you need to tell where the target is, is a good computer to do the math for you.
Note that ships fighting at relativistic speeds are just so unlikely.