I have been dealing with a similar issue and this is what I got.
Importing my car from the US to Switzerland via the Port of Genoa. My US insurance provider covers me for damages while shipping and driving. However, they do not cover for liability in Europe. That is the catch because most European countries could care less about the damage to your car, but you need that 3rd party liability.
I have been in touch with a few Swiss insurance companies who would insure me, no problem! But, they kept asking for the matriculation number. I would tell them I don't have one yet because I need to get the car to Swiss customs to get that matriculation number. However, in order to get the car out of the port and drive it, I need the insurance. So, its a catch-22. You can't get insurance without that number, but you need insurance to get the car to the place to get the number. If you want to pay a ton of money to have your car trucked from a port to your home then that is no problem as the trucking firms are insured. But, if you want to save a load of money and do it yourself you have to figure the insurance issue.
I did a search on
www.comparis.ch and selected every company I could and found one that would insure me without the matriculation number. You can also call some insurance providers who may insure your car under the chassis number until you get the matriculation number. One provider suggested I go to the Geneva License Office and ask them. But, I think the best advice is to just shop around until you get a good local provider. I'm dumping my US based damage insurance because if I get into an accident here I know my life will be easier dealing with a local insurance firm.