You could decide that it's worth spending a few weeks rewriting the core code from scratch, cleaning up the code in the process, and re-launch a similar commercial product with a new name and new license and without any of the original code.
-mouser
I don't have a dog in this race so to speak. I've thought about looking at CD, but haven't, so take this with that in mind.
Considering all that the developers have done on CD, and if the amount of code written is as much as you say, I'd say re-brand it as something else, clean up the code and remove any references to his code, and do as you will with it. Especially as you've already consulted a lawyer on this, and I
know that they are not cheap (one of the stopping points for several projects that I've considered has been legal fees).
Just my opinion. I think your license was more than fair, especially considering some of the other docks out there. I use a few, and many of them are licensed
per year to give you an example of what some others do. The only change that I see that you could have made is to offer license to those that did donate- therefore anyone who was whinging after that would be people who utilized the software for free and didn't donate.
That's my .02.