I never came that far to compile LCL (and / or Lazarus) for AROS 64bit but of course I always cared about 64-bit compatibility on the way to implement it (as far as possible).
Now with 3.2 out and Lazarus adapted to it with some minor tweak it was possible to compile LCL stuff for AROS64, even more complicated stuff like EdiSyn.
Sadly there are still some bugs, especially in the external components I use. For example the ATTabs, as you can see the caption in the Tabs are missing and if you click on one some strange things happen. After all it is somehow working but not completely fine.