Thanks for your answer and your proposal, and I hope people will be volunteers to do such an heavy work of coding, since even if I would have considered porting it, rewriting this from scratch is out of my coding level and of my free time.
Maybe you could release only the "core" source code, or even object files compiled on/for other systems (if allowed by the language you've used, of course... I hope it's not Delphi ^_^) to allow redesigning of GUIs other it.
I'd be very happy to see this kind of software run on non-Windows systems (or maybe even running on a webserver, which will be the coolest way) but I'll understand if you prefer to keep source codes for yourself, since it seems to have been a very huge amount of work.