It hasn't been tested on mac for a long time, but I see no reason why it would crash on a mac while it works on linux and windows. I'll try to test it on a mac somewhere this month though.
Compiled it myself for C++11 and 10.7+.
You probably did, but make sure that sfml and tgui are compiled in exactly the same way, with the same build flags.
But could you still try to move the event loop to the end of the main loop and to create less objects?
This might be stupid, but does it make a difference when using the BabyBlue style instead of the Black style?