I should perhaps add that I would always say "Please call me Mark".
Update (Wednesday, 00.03): Michael Pahl emails:
It's interesting that it does get a little more complicated than you've noted, however, when you add in a more basic rank in the North American system, that of "Instructor" or (more here in Canada, I think) "Lecturer." So a Lecturer here is nothing like a Lecturer in the UK, and as you've noted someone here can be called "Professor" when such a thing would be unthinkable in the UK!On the latter question, the answer is broadly yes, but it is not quite as formalised a structure as it seems to be in the USA and Canada. You'll often begin a job with "probationary status" and this will be upgraded to a permanent contract if you perform well, now including also doing a post-graduate higher education certificate. Others might take on a job with a fixed-term contract and then it be upgraded to a permanent contract in due course.
And I've wondered, does the UK have a tenure system?
My own experience in Birmingham was of a fixed-term contract appointment in 1995, for three years, to act as "teaching relief" for the then new dean of the faculty of Arts, Frances Young. My contract was then changed to a permanent one at the end of that three year period in 1998. So to use the American language, I was granted "tenure" after a three year fixed term contract. It's more common, though, to go the other route, probation and then permanent contract, something resembling "tenure track" in North America, though that term is never used here.