It's nominally a single movie, but it's structured as two distinct episodes -- somewhat thematically linked, and following directly, but pretty separate. Both are very small in every respect: quiet little self-contained stories of half an hour or so, with 3-4 actors, a little bit of CGI and a few sets.
The first one stars Elizabeth Lochley, and -- well, to put it gently, it's not JMS' best work. It reminds me of nothing quite so much as a mediocre episode of The Outer Limits. It's possible that it's setup for a larger B5-universe story (that's *always* possible with JMS), but it mostly reminds one that JMS' forte is long-format rather than short. I could forgive the weak acting and direction, but the script is pretty bad, and that's where I usually expect strength.
Fortunately, the second feels a lot more like a real B5 story: the script is far more tied into the larger B5 arc, revealing some new twists and fitting in nicely. It's better-written, and it stars Sheridan and better yet Galen (He Who Always Gets The Good Lines -- it's one of those techno-mage powers). I wouldn't say that it ranks as one of the best B5 episodes, but I wouldn't put it with the worst, either.
So the second half basically saves the disc. I still can't push it as something that everyone should rush out and buy, but it's an interesting little coda for the B5 fan, full of oblique meta-references, including an unsubtle hint at the end that there could be more of these if this one does okay...