Personally I find lazarus VT 4.8.7 fully compatible with the version I used in Delphi, so I would rather have bugs fixed in Lazarus/VT4.8.7/Carbon (it is my understanding the Carbon issue also causes problems in other controls in Carbon and since Cocoa is not ready then...)
Anyhow, maintaining compatiblity with properties (even if not fully implemented) should probably also have some priority, so it is as easy as possible moving a project from Delphi to Lazarus. (Since I have ported this part is no longer relevant for me, but I mention this to increase Delphi to Lazarus adaption / cross-compiler userbase)
Best would of course be if JAM would maintain Lazarus compatiblity, but if they have removed code then...