DothL is not just a Dylan Thomas quote, but also a nice little campaign from the first edition days.
In my experience (3/4 through) it ties in nicely with the published 3rd ed material. The adventure has no world-sweeping impact so is you are willing to use some 1st ed tropes, you don't have to change much. The campaign has Fimir and references to gods of law and a more obscure chaos god. I welcomed these things mostly for sentimental reasons.
The adventure ties in nicely with 'The Witch's Song" due to proximity (DothL starts and ends in Marienburg witch the rest of it set in the Wasteland). In my game, I had the group finish "Winds of Change" which promoted our Wizard's apprentice, who then was asked to get a book of lore in Marienburg. On the way there the group stopped in a little town called Faulingmere…..
Finishing The Witch's Song they thus had ample reason to continue to Marienburg which sets DothL in motion.
DotL features a giant octupus pretty eartly on, which is an opportunity to let the "Beast of Faulingmere" reappear (severly wounded from the tunnel collapse).
Happy gaming!