The chip and downloaded map should work the same, you need to mess with it for a while to get it figured out. Make sure you have the layers you want checked when you download them and they should be there offline. When I download, I check most of the layers and it looks like a big mess. Then, after you download it you can uncheck a bunch and get it where you want.
Having the private and BMA (MT) stuff on there is hugely valuable to me. I don't remember if they have the WY equivalents or not, but you can usually figure it out with just the private boundaries.