I've been having more fun with this than I can express. I think part of it is in the order in which I started reading the material:
1) Toxic Elven Smut (NTRPG release) - loved the map, the day/night encounter tables, and some of the monsters were born of fantasy-gone-horror. The system-neutral factor is a plus, as I'd mentioned. Not sure where (or how) I'll use the introductory story plates, but they should be used. Yeah, I'm hooked.
2) I read through the first couple of chapters of the Field Guide to Hot Springs Island. Brilliant stuff. The whole premise is that the chain of islands is discovered after a cataclysmic event, an unknown period of time after it was half-submerged by water...and other stuff. I got through the letters coming from the first people to stumble across Hot Springs Island (or, at least, the first whose notes survived), some correspondence to/from universities about studies made from these notes and personal accounts, as well as a couple of "alphabets" for languages cobbled together from said explorers' notes. Given what I'd already read in TES, some things started shifting into place in my brain.
I should preface this by explaining that this volume, a good-sized trade paperback, was sold as "something suitable for the players to read." Don't make the mistake of giving away any of this info without first digesting it yourself - or at least having a copy handy for your own reference. No stats are involved anywhere, but I feel the judge should understand the conclusion of "Oh, this must be where *this* happened" before players are given the clues to make that connection. For instance, Hot Springs Island was predominantly inhabited by elves prior to the cataclysm, but there's little to lead to this at first.
**NOTE TO JACOB: NEED THE FIELD GUIDE IN PDF FORMAT. SERIOUSLY. Being able to print off a single page (or portion thereof) to hand out would be *perfection*.
3) After an unwilling hiatus, I returned to the Field Guide today and picked up where I left off: Plant life. Some very cool stuff. Some had me cross-referencing Toxic Elven Smut, making some mental connections and leaps of logic, which got me flipping through ...
4) ... the "public" version of Toxic Elven Smut [2nd printing], which elaborates on some of the monsters with motivations and gives more info on the primary powers & influences of Hot Springs Island during its heyday. It had me flipping back & forth between the TES versions and the Field Guide, putting more things together.
5) Then there's the Lapis Observatory. Absolute genius. The whole thing is consistently presented in system-neutral format (so my DCC pals can see where I'm going with this). The observatory, one of the most easily-accessible areas from the main shores of Hot Springs Island, sheds a little light on the history of the island with the critters and artifacts. As for encounters: you can either roll to determine what kind of stuff is waiting on each floor, or compile it yourself -- and remember, while special attacks/qualities are noted, you get to stat them up to fit your needs.
After an hour or two of this fevered reading, cross-referencing, and reading some more, I feel energized (I want to run this for every one of our local groups NOW) and fully satisfied, as if I've just conquered a huge Cthonic mystery set forth by one of Bob's old CoC campaigns, with the levels of research and library use that my brain just went through. Damn if I don't want to start taking notes and flagging pertinent pages...but it'll need to percolate for a bit while I tackle some real-life adventures first.
Mind you, I'm barely halfway through the Field Guide. I still haven't hit the follow-up correspondence or known monsters [save for those appearing in the zines], or any number of other goodies.
My understanding is that Hot Springs Island is but one of many to be described in the upcoming compendium (likely a KS) for the Swordfish Islands. And I can't friggin' wait.