re: hope any of this helps
Ahhh… it is actually hardboard. Mostly because of my small budget – it was quite a lot cheaper than ply (false economy by the sounds of it!). Will see how it holds up initially and consider changing it. At least I can use it as a template and have already drilled the holes so I guess the hard work is done!!
I had considered going down the thin carpet route but have to say I agree with you about the looks. Kitchen/bathroom paint sounds good though – should give me more choice of colours/finishes/prices than specialist vehicle paint.
I like the idea of the vent though, ventilation is something I have been concerned about, might have a look in the diy shop.