this is a time that a call might help. I know the first year they offered the Canadian Residents tickets we needed 3 separate reservations for a family trip. Our son called and disney was able to apply the discount to the tickets and lowered his package total letting him keep everything else the same. we hadn't booked a room for our daughter yet and when I did that online myself, it came to the same price even though it didn't mention the tickets were CDN ones.
I suggest doing some mockup reservations, see what the price comes to if you book any or all of the discounts, disney math is a circle of h e l l !