Just as fiordy said it, Rinaldo, you just can't expect your pay-to-unlock software won't be cracked. The average FIFA 08 editor doesn't have the knowledge to bypass your protection, but there are cracking groups out there devoted to cracking and/or providing serials, making free for all what the developer wanted others to pay.
So what you're saying is that if such a group, that's not related to either the people here that support your work or SG or SP, cracks your editor, which it will, you'll stop providing any of your software for free anymore?
Well, this is a done case then. I'd love to respect your decision, but I disagree with the point you made there. It's as if you've made a promise to make 08 the last editor version you'll ever release on a free-to-try basis.
I, too, support the option to donate. I'm a supporter of open-source actually, and I donate to the projects I like. But even if you don't want to get the source out to the public, making your software shareware and threatening the community not to crack it is ridiculous. You just don't understand that the community doesn't get a say in this. Your tools will be cracked. Period. Accept that, and change your plans, or meet the dismay of disappointed gamers.