The most important thing is to hide all symbols when compiling wxWidgets on Mac.
When fluid has done it, the crash is gone.
We have same issue as with V-ray now. Thea dialogues will not close and neither refresh.
It is most likely caused by using IMPLEMENT_APP_NO_MAIN(MyApp) macro in AO. This allows just a single instance of wxApp. Our solution is to create our own instance of wxApp and to use wxApp::SetIntance( instance ); instead. When SU closes I do a clean-up and call wxUninitialize();
As far as I know Thea doesn't affect any plugin, so the solution works correctly.