Since I've been asked about this, I thought I should make a post here in order to clarify a couple of things about my two Dwimmermount sessions at August's OSRCon here in Toronto.
First, the rules will be my idiosyncratic LBBs + supplements mix. Any rules peculiarities will be explained beforehand and, if I'm diligent, I'll even type them up on a handy reference sheet.
Second, the two sessions take place on different levels of the Dwimmermount megadungeon. The Friday session is on level one, the Path of Mavors, and the Saturday session is one of the third levels, the House of Portals.
Third, I'll provide pre-generated PCs for all involved, including retainers. Those involved in the Friday session will be fresh 1st-level characters, while those involved in the Saturday session will be more experienced characters with 5000 XP each.
I'm still debating whether it would be worth it to lug all my miniatures and Hirst Arts blocks down to the con to use at the table or not. A big factor, too, is that I'm not sure I have minis for all the monsters on those two levels, which rather undermines the spectacle of the thing. I have some time to think about it, though.