Sorry, only thing left I can suggest is avoiding this issue by not using the all-in-one installer, but instead separately installing Python, Bazaar for that Python version, Qt, sip, PyQt, qbzr, and bzr-explorer.
Sorry, only thing left I can suggest is avoiding this issue by not using the all-in-one installer, but instead separately installing Python, Bazaar for that Python version, Qt, sip, PyQt, qbzr, and bzr-explorer.