Hi Jason,
Great question! We usually recommend that you use the built in Bookmarking template to automatically store/retrieve all variables.
However, you can store only certain variables. It just requires you to manually set up the map you want to store, and to be careful with the naming. I would definitely test test test. Here's a simple case with the actions you need (see attached image). You'll need to integrate it with the bookmarking logic (see the Bookmarking template) to have it work automatically onPageChange/onPageLoad. Of course, any variables that you DON'T include will be lost when you launch the lesson again, but can still be set by the lesson as the learner goes through the lesson again.
Hope that helps!