I think reaction to this piece is all about expectations.
If you're expecting a stand-alone episiode/movie that works on it's own merits... this clearly isn't that.
If you're expecting a grand revealing story about the mythos and mysteries of BSG, this isn't that either.
What it is is a simple look at the cylon perspective of the first 2 seasons of the show, as a complementary companion piece to the show and nothing more. On that level, it succeeds brilliantly.