I did end up finishing Dark Waters last night. Lots of pros, but some cons as well. The setting is fantastic, the custom content is overall very nice (nice resource for the community!), and the scripting of his various puzzles and mini-games was really well done. On the other hand, while the story is also excellent, its execution, particularly in the latter part of the module, wasn't very good. It seemed rather rushed, and was pretty confusing. There are also still some lingering bugs, but the show-stoppers seem to have been resolved.
Anyway, I've requested the review of Dark Waters with the NWVault Review Guild. Hopefully Adam Miller will agree. It might not be a gushing review, but I think it'll be very fair.
Update: Adam Miller wants to wait on the review until he fixes a few more bugs. Fair enough, though to be honest, I don't think that'll change the results much--I wasn't going to penalize it much at all due to bugs, as they didn't affect gameplay much. But who knows, maybe his subsequent version will make some other parts of the module work better. So I'm going to hold off on my comments for now. Hopefully he will eventually submit it for review.
Looking forward to playing Maerduin's The Birthday tonight...