[SuperJet]

I also run into problem with 0.6.31. When I launch calibre in the console under /Applications/calibre.app/Contents/MacOS/, I got these error messages:

calibre.app/Contents/MacOS/calibre
Python function terminated unexpectedly: dlopen(/Applications/calibre.app/Contents/Resources/Python/site-packages/PyQt4/QtWebKit.so, 2): Library not loaded: @executable_path/../Frameworks/QtWebKit.framework/Versions/4/QtWebKit
  Referenced from: /Applications/calibre.app/Contents/Resources/Python/site-packages/PyQt4/QtWebKit.so
  Reason: image not found
Traceback (most recent call last):
  File "/Applications/calibre.app/Contents/Resources/Python/lib/python2.6/site.py", line 147, in main
    return run_entry_point()
  File "/Applications/calibre.app/Contents/Resources/Python/lib/python2.6/site.py", line 115, in run_entry_point
    pmod = __import__(mod, fromlist=[1], level=0)
  File "site-packages/calibre/gui2/__init__.py", line 15, in <module>
  File "site-packages/calibre/ebooks/metadata/meta.py", line 11, in <module>
  File "site-packages/calibre/customize/ui.py", line 12, in <module>
  File "site-packages/calibre/customize/builtins.py", line 393, in <module>
  File "site-packages/calibre/ebooks/pdf/output.py", line 18, in <module>
  File "site-packages/calibre/ebooks/pdf/writer.py", line 22, in <module>
ImportError: dlopen(/Applications/calibre.app/Contents/Resources/Python/site-packages/PyQt4/QtWebKit.so, 2): Library not loaded: @executable_path/../Frameworks/QtWebKit.framework/Versions/4/QtWebKit
  Referenced from: /Applications/calibre.app/Contents/Resources/Python/site-packages/PyQt4/QtWebKit.so
  Reason: image not found

While 0.6.28 runs well.
And I can't see ".calibre_calibre GUI.lock" under /USERS/[myname]