Try not to worry too much, I know it's hard but they really do settle down eventually.
My Chinese go into their show pens just before I leave for a show and it's not uncommon for one or 2 of them to chew for at least half the drive to a show but they soon settle down either part way through the journey or once they're on the bench.
Bear in mind with your little Rosie, she's at home and you're there with her when you're trying to acclimatise her to the show cage so she's probably going crazy wondering why she's cooped up in a small space in such a familiar environment.
None of my Chinese spend times in their show pens apart from during the travelling and the show itself and, as I say, they tend to settle down fairly soon. I'd imagine that whilst you're travelling, and at the show itself, she will soon settle down so pleas try not to worry
When you go to the show and have her in the show cage, try not to keep going back to her, leave her to settle and enjoy the show as best you can.
First shows are always nerve-wracking but I'm sure you and Rosie will do great