[Definition] 'Donate, Donation.
Donations are given without return consideration. This lack of return consideration means that, in common law, an agreement to make a donation is an "imperfect contract void for want of consideration."
Please stop abusing the words 'donate' and 'donation'. If you want to charge for your software then great! You deserve financial compensation for your efforts however to claim a non crippled version is 'donation' is a lie. You are trading money for a license to use your software.
So in conclusion, unless your 'donation' version includes no functional difference from you 'free' version, can the use of the word 'donate' in the title.