[fpc-pascal] VirtualTreeview Mac (Carbon)

[CA Gorski]

Has anybody tried to compile the new VT port which requires 
lclextensions (Luipack) on Mac OS with target widget Carbon?
I did and wasn't succesfull. Problem is, you can't compile lclextensions.
Since I am pretty new to FPC my question is, is it the right way to 
generate a package (like lclextensions) which implements the missing 
Windows functions which are used by another package (here 
VirtualTreeview) for all widgets or should one change the later (VT) to 
use FCL/LCL functions so that it does not rely on Windows functions anymore?