Just watched this over on AXP, so copying and pasting.
It suffers from the problems that plague every fan film. Script needed a good edit to reduce the exposition and stuff lifted straight from Aliens (even taking the 'You know you don't need to say all that' gag into account), editing needed to be a lot tighter, acting from people who aren't actors.
But that said, the main characters (ie. the marines) all had a goofy charm - especially Kemp. The CGI was generally pretty good, particularly Gateway. But what made this not only the best Alien fan film, but one of the best fan films of any franchise - is the costumes and the hardware. All first class.
Very enjoyable overall.