Perhaps you have forgotten the way shareware originally worked. A fully functional version of a program was made available to whomever was interested in it. If they liked it and intended to use it again they were asked to make a contribution. Sometimes an amount was suggested by the author, sometimes not. It was then up to the user to do the honorable thing.
You are not providing a shareware download. You are providing a version with reduced functionality, a demo which is a very different thing. And you are assuming that I would not have paid you for your program if I planned on continuing to use it. While that wasn't true before, it is now. Maybe you should consider hiring a PR person.