Art: Illustrations are top-notch. Graphic design is fine, but I think the overall impression is a bit flat when all six pages get the same treatment. Would suggest treating e.g. the monster and item stat blocks differently so that there's some large-scale visual structure.
Writing: Does what it needs to do. The details are good, but the overall story structure is very cookie-cutter. The most glaring omission is any real personality for the NPCs. Even just explaining what's "off" about the Doctor would help. The other characters have no development at all, so a single sentence to give them a memorable personality or appearance would go a long way too.
Game Design: As with the writing, does what it sets out to do, but relies very heavily on a standard template.
Theme: Full marks. Windigo is a good, easily recognizable mythological monster and everything feels very Mothership.
Utility: Full marks. Would be perfectly fine as an introductory Mothership adventure.
Favorability: Well-executed for what it is, but a little too much of a Mothership cliché for my taste. I'd like to see what the same team could do taking a few more chances and thinking outside the box a bit on the next go-round.