Dave here. I just wanted to pop in and say hello, and to thank my fabulous co-host Tsukata for starting this thread and helping answer questions about the event! I've been preoccupied with challenge planning and getting props and stuff like that, so I am really happy that people have been online in the meantime expressing an interest! For those still considering the possibility of playing, as of this posting, there are still 3 pre-registration slots left.
As for the nature of the challenges, some are primarily physical (tests of agility or marksmanship), others are purely mental, and some are a mix of both physical and mental (such as 'gather all the pieces, then be the first assemble the puzzle'). The limitations of indoor space will prevent the challenges from being anything exceptionally grueling, but there will indeed be a fair bit of physical activity. As Tsukata already mentioned, there won't be any Gross Food Challenge at all due to a combination of concern about player food allergies and the convention center's 'no outside food' policies.
I'm also happy to see an interested volunteer who would like to help out rather than play. You're quite welcome to help. I'm sure there will be plenty to do, since some of the challenges (and possibly a few other aspects of the game) need set-up and clean-up in between turns. Thank you!
As for running in a shorter period of time... the timescale is going to be very compressed, as-is, in order to get the appropriate number of challenges and eliminations accomplished within the time available, plus time for the players to hang out together and plot strategy. Adjusting the scale (in terms of time spent and number of players) is something we might experiment with next year, depending on how things go this year.