Hi @DeusIrae,
thanks for doing this fabulous Let’s Play!
I tried to finish Cragne Manor some years ago, but got stuck about halfway through, so it is great to see now what I missed. And I had to chuckle a bit since I am currently in a similar situation as you back when you started the LP, with a teething baby keeping me up at night, so your posts kept me entertained through some sleepless times in the past weeks.
Now that the main part of this Let’s Play is over, I have to find other captivating stuff to read 
A bit offtopic maybe, but last night I stumbled upon some internal Infocom memos from the year 1985 where legendary Steve Meretzky proposed some game ideas to be implemented by Infocom in future IF games. One of them immediately caught my eye as it reminded me a bit of the approach later taken in Cragne Manor (although of course in much bigger scope there):
“THE VIABLE IDEA”
Genre: Mixed/Experimental?; Estimated Development Time: 6 months.
An idea I originally came up with as a way to produce a game in much less time than could normally be
expected, but which I think is an interesting idea even without that need. Basically, one person (the Editor) designs a tiny “piece” of a game — a couple of rooms, a few objects with action routines, maybe even a character. Working from this, in complete isolation, five (or so) imps would write a small mini-game (a
couple of puzzles, ten to twenty rooms) around that original core. The Editor would be responsible for integrating the five ideas together, blending the code, making sure that there wasn’t any gross repetition in the stories, and, of course, fixing bugs. I think that seeing how different people went in different directions from the same starting point would make for an interesting interactive fiction experience.
His game idea proved to be quite divisive within Infocom, with most people (incl. Brian Moriarty) being quite sceptical about it:
“Maybe too much of an “in” thing, appealing only to old, loyal customers???”
“My opinion is the same as the last time you suggested it; and I was right then, too.”
“Sounds dangerous. Lots of egos. I duck this one. Who needs the headaches?”
So unfortunately that project never saw the light of day, in favor of LGOP, Zork Zero and Stationfall, but I still found it quite interesting to read about a collaborative writing idea in IF back in the good old days already.