So the unpaid version is artificially crippled. That's not what I would call a "freeware" software.
No, Tuxy, I think there is a misunderstanding. The donor versions are betas. The beta-testers-donors donate to get to use the beta versions ahead of production schedule. Then, when it gets to the point for a new release, the beta version is released as a public version. There is no crippling going on. A new, fully-functional public release is made every few months or so. The donor version is basically a beta-preview.
FreeCommander has NO license or registration codes to govern any kind of feature-crippling system. It's always been this way. It's called FREECommander for a reason.Here is from the FAQ page
Is the FreeCommander free also for commercial use?
Yes it is, you can use it free of charge for private and professional purposes. You may not however sell it for profit and you may not bundle FreeCommander in other software packages without affirmation of the author.
However, to give you some credit, this is from the FAQ, too (but I don't know if this is still the case anymore; it might be; I've never tested it):
The functions of the donor release compared to public are the same with the exception for searching in the “PDF” files.