Re: how does the timetable work?
Well, once you've accepted your offer, you should check out the subjects offered in your degree and which are compulsory and then note them down. You can do this online by looking at the degree structure and the relevant handbooks.
I cant remember if there was a list on enrolment day, (there might be) but I remember I wrote down the 8 subjects I planned to do in first year beforehand and then filled out the form. Plus its quicker that way. Enrolment can be really long and tedious if you're not prepared.