Hi, I have not read through the whole thread, as I am too lazy, but a word of warning if I may.
Do NOT try to register a truck as a Motor Caravan from the word go, well if it is a T244, as it will fail! Go for Private HGV first, then change it after the build.
I can't remember what vehicle you have, but if you try and register an old vehicle under new rules then all sorts of safety rules come into play.
Have a gander on my website and see if it helps.http://home2roam.uk/wp/registering/