Hi Codive,
The short answer on warranty is that it only applies to the original purchaser. You can read the details in the trailer manual. A copy can be downloaded
here.
The Canadian Arctic Package is also known as the YETI Package. It provides heating pads on the holding tanks, heat tape on the underbelly portion of the fresh water feed line coming out of the fresh tank, radiant insulation in the front and rear caps, and may include radiant insulation in other places like slide room floors. If you plan on camping in sub-freezing weather, you'll definitely want it.