I can't reply to you precisely about this, since the issue is not really relevant to FSDT Zurich, but rather it's a question about how properly remove FreeZ.
I think the reason why you are still seeing stuff coming from FreeZ, even with the scenery disabled in the Scenery Library, might be due to the fact that, perhaps, FreeZ also installs some of its files in other scenery folders that are always active, like the default scenery. That's just a guess, but it's the only possible explanation if you still see FreeZ elements with the scenery disabled.
Or, it might be you have a double entry for FreeZ in the Scenery Library that you haven't noticed.