Looks like you have an unsatisfied dependency on pango. (I didn't know that pango had python bindings.)
The CGError is interesting. Do you get it if you just open a python shell (from inside a jhbuild shell, of course) and import gtk?
Yes. I get the same error (except the last 3 lines: ImportError, Fatal PYthon error and Abort trap) when I just import gtk from a python shell inside jhbuild shell.
Where's _RegisterApplication() come from?
It's not a part of my application's code. So, it's probably coming from gtk itself.
Did you build gtk-mac-integration again after you got pygtk going?
No, I didn't earlier. Now, I did "make && make install" from gtk/source/gtk-mac-integration-1.0.1. Still the error remains.
Am I building it the right way?