How much teaching in Sweden is done in an intensive block mode? According to somebody at my university, the entire higher education system in Sweden is taught using an intensive "block mode": instead of students enrolled in multiple courses/subjects over a semester, they enrol in just one subject at a time for three or four weeks, then move on to the next subject.  I'm trying to find out whether this is in fact true.  Does anybody here know about university teaching in Sweden?  Thanks.
It varies, most likely between universities but also between disciplines. In my field, a social science, the bachelor level has full-time courses except the final semester in which two courses run in parallel. At the advanced level, the students take two courses at the same time. But in a closely related master's program, courses are given the way you describe. 

At my university in the STEM field, I believe it is more common to be enrolled in 3 or more courses simultaneously. 

For your specific situation, it should, however, be fairly easy to check online.