(my opinion shifted considerably after reading the scenario...)
All of the critiques listed to-date added up to a very negatively received scenario. Overall, it felt contrived and was tedious for a non-optimized mid-tier group.
A scenario that I wish I had never played and would never want to run and advise anyone else to avoid playing winds up as the least enjoyable scenario I have played to date. (This changed after reading the scenario - it motivated me to want to run it so I could try a bit harder than my GM to do it properly.)
This type of material (GMing, ultimately), encountered regularly, would discourage me from playing PFS entirely. As it stands, I reconsider my interest in higher tier content. Congratulations on a clever, well-built scenario that eroded any sense of pleasure as a PC (thanks to the GM).
Edit: After reading the scenario, it appears the GM used a flip-map in place of the proper map for the final encounter, as well as applying the 4-player modifications incorrectly (affecting NPC reach and size) and positioning the NPCs in a highly disadvantageous location (immediately adjacent to all the hostile NPCs) relative to the intended scenario placement.
Edit: After re-reading the scenario, the GM ran the first encounter ignoring the tactics written and somehow giving 2 critical NPCs the equivalent of blindsense/tremorsense/scent when the only thing they have is "blind-fight". How a highly experienced Venture-Captain GM can make so many egregious errors, I do not know. This was the 3rd time he reportedly was running this at Origins, so that would be 18 players subjected to the thorough incorrect running of this scenario.
What we have is an experience that goes from a no-star review, to a one star-review, to a two-star review, to a tentative three-star review. I'm thinking this scenario is considerably better than what I experienced, but I will likely never experience it as intended as a player. A cautionary tale, perhaps?