I've heard about two transfers in St George's back in 97. One was from Israel (Sackler's, I think) and one was from Ross. The Ross student was married to a SGU student, I think. I'm not too sure about it. In 97, I asked Dr Paparo (assoc dean at St Georges, histo prof and my neighbor at Maffiken apts!) if advanced placings were allowed at SGU and he said that it's rare. However, as a former student at SGU and I know how they work, I'm inclined to say that it is totally possible to get into SGU after attending another foreign school, but the real question is, will you be allowed in with advanced standings or will you be forced to repeat your courses? I bet that you'll have to repeat. It make better financial sense for them to have you repeat and it makes good sense for them to accept you because you've proven yourself at another school. They don't have to worry about you dropping out after flunking all your courses.
Spaces do open up in every class due to decelerating students. About 5 students in each class decelerates into their 5 year program.
The best thing is to try and see if they'll take you. Hope this helps!