Are cameras allowed of any size? (Mine is like a medium size)

I was just there last week and yes cameras are permited

No FLASH photography during most shows and NO video allowed, but most people ignore that and record with phones...

Depends on the event...but it's a big enough space that it's generally nit policed.

Yes we ware there yesterday and we had camera no worries we had VIP ticket with box sitting

No.

definitely check before heading down

This actually depends on the event. Check with the venue before bringing the camera. To be frank a cell phone will not be effectively stopped but they did tell me not to film (even without flash).

Not a midium format film camera for sure, but a mid size digital camera is no problem.

Not sure but everyone had camera phones.