The issues with this adventure are numerous.

1. The connection to the first adventure in this series. It ignores the portal the players find in the first adventure and makes them find a new one. It would have strenghtened the continuity if the players used the same portal.
2. The map. There are no labels. Why?
3. The "Playing the Pillars" sidebars are missing. I actually hate this format and would rather find all the information in the text, but not including it leaves the DM guessing. They are present in the bonus objectives.
4. The window in the captive's cell that reveals Shar's Perpetual Darkness. Is this a set up for the next adventure? Should characters have access to this room? If so, there is no description of the scene. If the characters are not to have access, how do I prevent them from gaining access?
5. The Shadow Dragon. Are the adventurers supposed to encounter the Shadow Dragon? There is no stat block and no description of how this encounter is supposed to work?
6. Editing. Read the creature blocks for bonus objective B.
7. Timing. The entire adventure with bonus objectives did not take four hours.

I had to read this three times before I could make sense of it.