Okay- I'll do my best to make it as general as possible then..
So from my understanding, students are allowed to take other graduate level courses- from different departmetns, other schools ,etc to count towards their degree.. as long as they are graduate level.. But the thing is- it all depends on how much extra room you have- as in- for the Global Health Track, it is a pretty rigorous course load with a lot of core/elective classes within the track/dept itself, so there aren't many leftover "electives" for one to take in another dept/school. But if you have the space, then you are allowed to take the classes. Apparently you will get a course listing of all the classes available from the different schools. You can take undergrad classes, but it won't count towards the degree and you have to pay for it(because columbia doesn't have a flat tuition)... SO for other tracks that don't have as many requiremetns, you have space for more electives in other depts/schools..does that make sense?
i talked to a student who said the advisors are willing to work with you to help you take courses that suit your needs as well.. she was in global health in the SMS dept but is taking 2 Pop/Fam health classes this semester
As far as housing goes- the campus is located in Washington Heights-(subway stop -168th and broadway) and there are dorm style as well as apartmetn style housing options located in that area. We are not allowed to apply for the housing on the other campus.. Housing is done on a first coem first serve (from when you turn i your deposit) as well as priority given to those coming from farther away... the apartments have 2 bedroom and 3 bedroom and rent is undervalue..