I don't think you can, at least without being very computer savvy. I have a chip for lakes in Canada when we go fishing. I just hooked it up to my computer and could not figure out a way to get the data onto the GPS device or the computer. It appears they have a block on it.
I seem to remember asking the folks at HuntingGPSmaps about. If you're looking into purchasing the software just call them up and ask. In my experience they don't care which way you go, they just want you to get what works best for you.
If you're interested in Birdseye you will have to download it to an SD card. Therefore, if you want any other maps you'll have to carry an extra card, which would be quite cumbersome to use that way. I love having my own SD cards to put whatever I want on them.
Just today I downloaded, from the KS Dept. of Wildlife website, all Walk-In Hunting Areas in the state. I know have 4 different mapping programs on one card and can cycle through which ones I want to access very quickly.