One other thing to watch out for on the Mac. If you have Qt libraries installed on your machine, and they are defined in the DYLD_LIBRARY_PATH environment variable, and they are of a different version to the ones shipped with the glade.app bundle, then you will most likely get a crash if you try and run Glade from the command line rather than click on it in the Finder.
The reason is that when clicked on with the Finder, OSX environment variables are ignored by the app, which looks for and finds the Qt libs in the .app bundle.
When run from the command line, the executable knows nothing about the .app bundle libs, and looks at DYLD_LIBRARY_PATH instead. And if e.g. you have Qt 4.8.2 on your system, but Glade was compiled with 4.8.6, it will print an error message to the terminal and die…