Ended up buying points instead. I don't know why I can't play it, lots of license fuckery, probably has to do with my old 360 but I don't know my friend's email info so it's all a bit complicated.The rewards system would take too long to get 200 points, so you'd probably have to spend money.
Why can't you play the full version though? I buy games and my roommate plays them all on her account fine. Did your friend transfer the license to another Xbox?
Btw, I'm thinking about Geo Wars 2 as well, but the demo wasn't that exciting. Are the other modes better?
Well, it's one of the must have games on XBL. Generally all the modes have quite a bit of variation. There's the 3 minute get as many points as you can mode with infinite lives, King where you only have one life but can only shoot when you're in "hills" which eventually disappear forcing you to move to another hill, a pacifism mode where you can't shoot but must move through gates which explode to do damage to enemies. On top of that it has Waves from PGR4 and the original Retro Evolved infinite mode improved, and one other mode I forget. If you don't like the premise of the gameplay as a twin stick shooter you probably won't like the rest of the game, but there are a variety of modes in the full game. A steal at 200mspts.
It also has up to 4 player co-op or competitive for all modes. Local and maybe online. The Game Details on the XBL page will probably be more specific with that.