If you want to see how "free" makes money, then go to your smartphone and open the store app. Look at the number of free games available for it. Those "free" games are making not just millions of pounds a year, but billions. If mobile games are a bit of a conceptual leap from EDA software, how about this: Red Hat made its money out of supporting Linux, and is currently worth $10 Billion.
I want to underline what someone else said earlier about giving credit to people who upload component models. If they really want their sharing thing to take off, then what better way to reward contributions and build the product? Time-limited functionality should be a no-no though, you should be able to upgrade it permanently. If functionality really is so dynamically configurable without software or even OS restarts, then that would probably indicate something as simple as a registry setting. I could see people renting all the "toys" for a week, downloading libraries to cache, and then snapshotting the software, and blocking the license server. Lets face it, if people can get around oscilloscope embedded firmware upgrades, then PC software will be a walk in the park for them.