Gunwolf,
Once you're in there, there is no escape and 14 weeks is far too young for puppy joints to do a whole day on her feet.
At my vet's, I have seen the effect of thoughtless owners dragging your puppies round a show for a whole day and it's not pretty.
At 14 weeks, it should a little and often, not 8 hours in the high 20's degrees.
All,
For your information, it has been announced that the 2015 show will be Harewood House near Harrogate, NOT BELVOIR.
Harewood is lovely but was the infamous venue that was cancelled due to the rain in 2007.