Girl Genius Game: Castle Mechanic

Here's a notional mechanic for the castle. Its primary purposes are:

To avoid requiring 1 GM per group within the castle;
To make the castle a large (or at least, larger) in-game space without turning it into a nebulous meta-box where only GMs know where everything is.

("Being an engaging sub-game" is not one of its priorities. If it ends up as such, that's fine, but it's not the point. The only plot-relevant in-Castle locations that I can think of offhand are the chamber with the Mirror and Abner's cell; everything else is pretty much just a physical space which may contain people, objects, danger, and/or ambiance, and the game will be unaffected if nobody ever sees it.)

Basic notion

Divide the room up into two areas.

The first area is the passageways of the castle; it consists of (ideally) obstacles like chairs, and some number of large manilia envelopes representing doors shoved under / around / on the chairs or leaning up against the walls. (Each one has a picture of a door taped onto the front so they're at least vaguely visually distinguishable.) Players may not move the envelopes, but can open them, looking into the rooms.

In each large envelope is a piece of paper with a brief (1-2 sentence, max) description, and a letter-sized envelope labelled EXPLORE or somesuch. To look around, you take out the EXPLORE envelope and walk over to the second area, which has 2-3 taped-off (or otherwise divided) spaces used as realspace when folks actually go into a room to do stuff.

Envelopes may contain:

Further description;
Item cards;
Traps, resulting in either "See a GM!" or "Roll vs. an N or be hurt, causing [effect]!" or whatever.

If a player wants to interact with the room in some non-standard way, they'll have to grab a GM.

(Possibility: The above areas could be the "less dangerous" parts of the castle, with a couple of doors which have notes within saying "This way seems foreboding. If you wish to proceed further, get a GM." Actually, we can have GM-mediated expeditions through hidden areas of the castle just by having egresses (secret or not) out of some rooms.)

GM control

GMs may move rooms occasionally, to represent the fact that the ways of the castle require some learning. (Heck, who knows - it might actually change configuration over time. It's not at all implausible.)
Not all rooms need be "in circulation" at once! In fact, some rooms probably ought to be reserved - Abner's cell, so that it won't be found by random chance early in the game; a couple of interesting rooms that can only be found via GM-mediated expeditions (with greater detail / involvement / challenge); etc.
GMs would need to provide some guidance to (at least!) Sarah, probably Beetle/Merlot, and maybe the others who've been in the castle - they have familiarity. My instinct would be to give Sarah a GM-level cheat sheet and permit her to access hidden rooms simply by asking a GM; to give Beetle/Merlot some pictures of the doors to rooms they're more familiar with and a feel for some of what's in the castle; and to say that Othar's squad didn't really get enough of a feel for the place to know their way around.

If there is lots of Stuff in the castle, players should be reminded that just because they can carry half a dozen index cards doesn't mean they can haul around an anvil, two hammers, a localized metaconverter, a big box of spare parts and a full fishbowl...at least, not without appearing comically overburdened. :)

Getting it done

Obviously, the above is a non-trivial amount of work, but it's also relatively encapsulated work - it doesn't really need to interface with much of anything else in the game, for the most part. If you like the notion, I ought to be able to put it all together myself:

Castle Materials

N "doorways" (big envelope w/picture, GM code, description [inside], EXPLORE sub-envelope [inside]) *Ideally, two sets - 1/run)
N rooms (EXPLORE sub-envelopes w/GM code, description / stuff / traps [inside]) Definitely two copies of these, since their contents might change substantially during run #1.
Wall signs: "CASTLE HALLWAYS", "CASTLE ROOMS" Ideally, two sets; one is workable.

GM Materials

One-page GM cheat sheet for the contents of the above (1/GM)
GMing The Castle - Brief guide for "Running impromptu castle explorations" (1/GM)
GM Castle Setup Checklist (1/run)
Binder with interior descriptions of each room, with GM gloss. (2 binders - odd/even?) Can also be place to jot state of things.
- Reminder at top to initial notes!

Player materials

Exploring The Castle - Player instructions for exploring the castle (how many? min 3-5, for posting prominently about the castle space; perhaps 1/player, perhaps 1/GM? Remember two runs)
Castle Rooms - Sarah - Cheat sheet for Sarah (x2 for two runs)
Castle Rooms - Prof - Cheat sheet for Beetle/Merlot (x2 for two runs)

Optional additions

Signs indicating stuff in the hallways (triggered traps, remains of prior expeditions, live traps (ow!), evocative descriptions, etc). [Darker checks GM policies] - Hey! You can put stuff on the walls if you bring your own masking tape! Sweet! That'd allow a lot more space for doors, and permit them to be hung at eye-height rather than making it seem like an Alice's Wonderland of tiny doors all 'round the floor. As with doors, GMs who feel like it (and have spare moments to breathe) can move these around if they feel like it. Ideally, two sets; one is workable.
~~"This door is locked / unlocked" cards to hang on doors.~~ Locked doors will be handled via the high-level room description.

Other notes

There will be some locked doors in the Castle. Items (eg, Lars' lockpick ring) or abilities relevant to such may be worth including, though there's always the "brute force" method of dealing with 'em. :) Locked doors will say "You can unlock with a key opening A, G, or H". "A" (for "all" and "Amagog") will unlock any normal-sized door lock in the castle (master-key); otherwise, it's mostly "each room w/lock has a different lock".