Talk about the proverbial can of worms :)
Getting registration for foreigners in most of the states is a losing proposition. My good mate from the Sydney area came over and obtained a South Dakota driver's licence (yes, with a c, not s) in order to be able to eventually register his RV there. But that required an I-94 visa rather than the usual tourist visa. And you'll need something else as well if you want to stay for more than 6 months. But I digress..
As an example, my home state requires proof of residency in the county in order to register a vehicle. Talk about having to jump through hoops in order to give them money!!
I certainly don't want to discourage you as others have apparently successfully done what you are trying. Just seems like they all disappear back into the woodwork when asked to elaborate.
Oh, and as for insurance, check out Explorer RV. They offer Coach-net roadside assistance as part of the policy.
Feel free to PM me if you need more info, assistance, encouragement, etc...
