I wish I knew as much as you claim to know, I'd be a much better person .......... now must get back to my spliff

It proves road worthiness in the same way an MOT does, i.e it says that on the DAY OF THE TEST, the vehicle was roadworthy, doesn't say anything about it's state the next day or any other day thereafter.

You believe the standard required to pass an ITV is comparable to that of an MOT? What about driving examination standards......on a par as well would you say?

I have no idea on comparisons, just that the two say the same in relation to the laws of the land, same for the driving test, can't compare them at all as I have no idea of the Spanish requiremants.

just to keep the thread going--In the UK you can buy a lhd car with Spanish plates on from www.lhdplace.com How would you go on with that?

Have you spoken to the company because they offer a fair amount of advice.

If you do make sure all the proper paperwork is with it, and a certificate to say there are no embargos on it.
If the road tax has not been paid, speeding and parking fines etc come with the car, so you must make sure all is paid up to date......