I'm just seconding what Phil said.
I've tried building Lazarus with Cocoa, and it's unusable.
Now, it's not like the Carbon build doesn't have issues... Several GUI issues, especially in the settings forms, but it generally works.
I honestly wish there was something I could do.
Without Cocoa as an option, I don't see how I could stay with FPC/Lazarus for GUI applications, as most of what I do (GUI-wise) needs to be cross platform or Mac specific.
I just tried and can't rebuild Lazarus with any of the other widget sets to even get a feel for how well they work.
Without a big corporation using Laz and willing to put man-hours into it, I don't see how this will get better, not when it's been nearly a decade and there's an active $3k bounty for finish up an existing implementation.
I can offer a percentage of income from Cocoa based applications in the future, but can't put a lot down up front, and I doubt running a garage sale will get enough to really pay for development.
The only other option for me is to learn the inner workings of LCL, Lazarus, FPC, Cocoa, which I wouldn't mind but isn't feasible to get something within a reasonable timeframe, seeing as current apps are getting warnings from MacOS about being Carbon/32bit.
How do we convince Google that it's the wave of the future?