I played this mod as a player and ran it as a DM. When I played it as a player the entire thing took 2 hours with both bonus objectives. At the time I thought the DM must have ran it incorrectly, but unfortunately he was right. I managed to stretch it out to 3 hours when I ran it, but the party had accomplished all the objectives within 2 hours. Part of the problem is that there is a mechanic at the beginning that allows the players to essentially bypass all encounters until the final objective. Even if the players do have to fight through the encounters, the enemies are way underpowered.
Continuity is an issue with many of this season's adventure series and this series is particularly bad. The adventure begins in the prisoner cell. I assume this is meant to be the same prisoner cell from Escape from Vanrakdoom. There is a window that looks on the Forge in this adventure, but it looks on Shar's perpetual Darkness in the Vanrakdoom adventure. In any case Stone Shape would bypass the entire trek.
In the final battle, how many vampire guardians are present? The adventure doesn't say. It says to add one for a strong party, but the text does not specify how many for an average party.
[2 of 5 Stars!]