If you can demonstrate that the problem existed during the warranty period then I would expect that Mazda would be obliged to fix it.
If you are not getting anywhere you can consider binding arbitration. check out
http://camvap.ca/eng/index_1.html Arbitrator can compel the manufacturer to fix the problem or provide compensation or to buy back the vehicle.
I have initiated an application for arbitration against Ford regarding the Escape air vent smell problem. I'll let you know how this goes.