You are most welcome and thank you for pointing this issue out early! The individual who I had test the Xbox pads got a earful today at work :)
Yip, the demo 'Party Games' mode is limited to 2 players, 1 min and no multiple game tournaments. There's also no access to Timetrial and Sandbox modes in the demo and obviously only the first 10 challenges.
I should really deactivate the Joypad3 and 4 on the Control Setup for the Demo. It isn't doing any harm so not up there in terms of priorities at the moment.
Cheers
Stevie