Many months on from when I suggested taking my cat on holiday & 4 months into the holiday....
Flynn is a happy happy van cat, he treated his basket (much used at home) with utter contempt and sleeps accross/ovver/on top of/next to DH & I in bed - his litter tray migrated to the shower tray for ease
He walks on a lead - after 2 days of dreamies he walked well, now he walks for about 20-30 minutes up to 3 times a day, unless he isn't in the mood when he demands his lead, we get it fasened & the he sits & licks his bum 
We went home for 2 week & we found him crying on the step of the van (on the drive) to get back inside it
I created a 'cage' off the boot at the back which he also ignored...he prefers the dashborad next to the windscreen for maxiumu sunshine!
He had met many, many friends - dogs, peacocks, men, women & children and broke lots of hearts - including a large black (lab sized but mongrel) dog where they spent a good 10 minutes smelling each other bums!! Another dog had cuddles for a few minutes before hating each other! And a squirrel caused the fluffiest tail you have ever seen on a siamese
So it worked, although we do wonder if when we move back into a house if we will still have to walk him on a lead
Just thought I'd update you all