We playtested this adventure using OD&D/S&W and it was great fun. Definitely A-grade Olde Skool goodness that oozes with atmosphere and dread. It's got a Ravenloft feel, but its very open ended so your crew can chuck the various mysteries and just loot the place and run.
$15 bucks for the print version & PDF
https://www.kickstarter.com/projects/cryptic-codex/a-blight-upon-sombreval
FYI, our crew failed to save the day, but we stole lots of flashy goodies and pissed off the Evil Dudes which was very entertaining, but my Dwarf Cleric did get his head exploded by a lightning elemental.