I don't know why "Select an Installed Product" doesn't show my current Membership installation.
In any case, I spent a lot of time learning and creating that site and now I see there's something new. My guess is, I can't just install it and have my current membership files working with that new version.
And so what should I do?
My thought would be to install in in another folder and recreate it, but when I go to install Membership 2, it just says it can't because there already is a Membership folder and doesn't offer the option of installing it elsewhere.