I was pleasantly surprised by the amount, nearly 60 pages, of pure adventure material (plus three supporting articles)! I haven't yet had time to read the whole thing through, but I skimmed through the first few pages. I liked the dividing into clear sections and acts.
I got the impression that this is a somewhat challenging adventure/campaign. For how many characters is it meant? Also, are the characters assumed to be well equipped and experienced?
Edit. Ok, p. 43 designer notes says:
Peran: Heart of Darkness is not intended as an introductory
adventure for inexperienced players so a GM wishing
to use it in that way should consider scaling down some of
the challenges to match the skills of starting players (and
If you read on from the section you've quoted (I con't think I edited it out of the final draft) then you'll find a range of FFF NPCs from which the various HarnCon and IviniaCon players chose. Have a look at those - downloadable from Lythia.com - and they'll give you an idea of the 'strength' of character they've been play-tested with.
It's fair to say they've been play-tested by some pretty dedicated RPG'ers (you don't travel to either Con on a whim) so there wasn't anyone who set out to try to hack'n'slash their way through the early stages. The 4 or 5 groups that have played it tended to the thoughtful, interactive, sorts who didn't come at it like bulls in china shops. With the exception of that 'Fool of a Cook' throwing a pebble down a hole ... You know who you are ... but you'll also know that the drums that echoed back up were entriely invented and not actually to be found down there!
In truth I'd be very glad to get feedback from other groups. I'm particularly aware that it's not been GM'd by anyone else! Anders is going to give it a whirl in September but if others have feedback ... great - let me know how it plays in the 'real', non-Con, world.
I'd say you need at least 4 and probably no more than 6, but when you read it you'll see places you can scale it down for 2 or 3 players. Alternatively you can avoid the 'Watcher in the Woods' scene so there's nothing to distract them later on. You can also weaken the final challenge (I won't say anymore lest I get into spoilers) in order to cope with fewer pairs of hands.