I had posted this review in the discussion section, because I wasn't able to review it until I had purchased the PDF (I had purchased the physical copy at a local game store). The module includes a code to download a PDF, but the code was expired. Goodman Games sent a valid code to me, so I can now post my review here!
I read through this entire adventure tonight. It is fairly short. The book is 16 pages with 11 of those being the background + adventure, 1 page of monster stats (there are a few additional monster stats included in the adventure pages), 2 pages of "concluding the adventure," new sub-race, and a new background, then 1 page of maps.
There are a few things that I really like about this adventure. First, it is a mini dungeon crawl. However, not every room has an encounter. In fact, maybe only 1/3 of the rooms have encounters. However, all rooms have descriptions and elements of interest. I tire of crawls where every room has an encounter. Second, I like how the encounters include descriptions of how the creatures will approach the combat. The DM is obviously free to change this, but it is nice to have this included. Third, even though this is a mini adventure, it feels that the author(s) put quite a bit of thought into it.
I am most likely going to modify this a bit and include it as a side adventure in Out of the Abyss. I don't think it'll take much to adapt it.