Have been lurking on this site for ages - got my Move up! white yesterday - thrilled - just thought I would show how I intend to transport my dog Jake. Bag folds up as can be seen in last photo - Jake is no longer in the car!!
Got it from roof box - http://www.roofbox.co.uk/dog-bag/ - mine was the large size you might get away with a medium - have a look at their offers seconds section mine was an ex display model and was fine (also had a display model in my previous car and had no problems with it).