Where can I find consolidated information on everything to do with being in a B.Sc. or B.A./B.Sc. program ?
It is worth taking a look through this handbook developed by the Faculty of Science.
A "D" grade means a conditional (non-continuation) pass. All courses required in a program must be passed with a grade C or higher. A "D" grade can be cleared either by passing a supplemental exam or retaking the course. In this last case, additional credit will not be recognized for a course already passed even if the grade was a D. It is not recommended to take a higher level course if you obtained a D grade in a pre-requisite course.
Yes. At a later date, you can modify your registration until the end of the Course Change (add/drop) period.
I have completed all the requirements for one program (ex.: honours), but I am registered for a different program (ex.: major). Will this be automatically recognized for graduation?
No, it will not. You can only graduate from the program for which you are registered. You will not obtain an Honours degree if you are registered in the Major program, even if you have a CGPA higher than 3.0, research experience and all the additional courses required by the Honours program. It is therefore of utmost importance that you verify your registration at appropriate time before graduation.