Should I worry about running a Carbon app on El Capitan?
I still have a few user inteface controls that won’t work on Cocoa and I have not found and implemented replacements yet.
for the most part Carbon apps do work, there’s a lot of cases where they will fail and they’re treated as third class citizens by the OS.
Most of the trouble we’ve encountered is deprecation of functions.
For maximum compatibility use Cocoa 64-Bit, even Cocoa 32-Bit is a second class citizen on OS X Cap.
The main one is StyleGrid. I have a LOT of code using StyleGrid and have 4 grids in my app.
Unfortunately the developer is not keeping it up to date and it doesn’t work on the newer OS’s.
Time to take a look for a replacement, or to even use the built-in Listbox (it’s actually pretty powerful)