Here is what I think, other members feel free to correct me if I am wrong.
@Olkina
1. Your temporary status as a student starts from the day you are physically in Canada.
2. I am not sure what off-campus work permit are you referring to. I do not think you should list off-campus work permit while you were still a student since your main status was student. UNLESS this is a post-graduate work permit, then you are considered as a temporary worker, not student anymore.
3. Country of destination is enough.
All in all, every single trips (including day trips) should be listed in the date calculator.
All statuses should be bracketed within the eligibility period (i.e. if you are on work permit starting from Feb 12, 2012 and the eligibility period starts from Mar 01, 2012 then list Mar 01, 2012 in the table.