Hi, Could you also copy and paste the full output of: $ relax --info This will help a lot. I am using Python 2.5, Python 2.6 and Python 2.7 (the last is via an application framework at /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/bin/python which I use to create the monster DMG file). In all three, the GUI is working fine. Well, the Python 2.5 version refuses to quit, but still works. I have pasted the 'relax -i' text at the end for reference. This is from the repository r15640 revision of the 1.3 line. Regards, Edward /usr/bin/python2.5 relax -i relax repository checkout Molecular dynamics by NMR data analysis Copyright (C) 2001-2006 Edward d'Auvergne Copyright (C) 2006-2012 the relax development team This is free software which you are welcome to modify and redistribute under the conditions of the GNU General Public License (GPL). This program, including all modules, is licensed under the GPL and comes with absolutely no warranty. For details type 'GPL' within the relax prompt. Assistance in using the relax prompt and scripting interface can be accessed by typing 'help' within the prompt. Processor fabric: Uni-processor. Hardware information: Machine: i386 Processor: i386 Endianness: little Total RAM size: ? Mb Total swap size: ? Mb Operating system information: System: Darwin Release: 10.7.0 Version: Darwin Kernel Version 10.7.0: Mon Mar 28 13:34:53 EDT 2011; legacy kernel v7 :xnu-1504.9.37/BUILD/obj/RELEASE_I386 Mac version: 10.6.7 (, , ) i386 Distribution: Full platform string: Darwin-10.7.0-i386-32bit Python information: Architecture: 32bit Python version: 2.5.4 Python build: r254:67916, Jun 24 2010 21:47:25 Python compiler: GCC 4.2.1 (Apple Inc. build 5646) Libc version: Python executable: /usr/bin/python2.5 Python module path: ['/Users/edward/relax/relax-1.3', '/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python25.zip', '/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5', '/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-darwin', '/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-mac', '/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-mac/lib-scriptpackages', '/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python', '/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-tk', '/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-dynload', '/Library/Python/2.5/site-packages', '/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/PyObjC', '/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/wx-2.8-mac-unicode', '/Users/edward/relax/relax-1.3/extern/scientific_python/darwin'] Python packages (most are optional): Package Installed Version Path minfx True Unknown /Users/edward/relax/relax-1.3/minfx bmrblib True Unknown /Users/edward/relax/relax-1.3/bmrblib numpy True 1.2.1 /System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/numpy scipy False wxPython True 2.8.8.1 /System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/wx-2.8-mac-unicode/wx mpi4py False epydoc False optparse True 1.5.3 /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/optparse.py readline True /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-dynload/readline.so profile True /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/profile.py bz2 True /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-dynload/bz2.so gzip True /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/gzip.py os.devnull True /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/os.py Compiled relax C modules: Relaxation curve fitting: True /usr/bin/python2.6 relax -i RelaxWarning: os.popen3 is deprecated. Use the subprocess module. relax repository checkout Molecular dynamics by NMR data analysis Copyright (C) 2001-2006 Edward d'Auvergne Copyright (C) 2006-2012 the relax development team This is free software which you are welcome to modify and redistribute under the conditions of the GNU General Public License (GPL). This program, including all modules, is licensed under the GPL and comes with absolutely no warranty. For details type 'GPL' within the relax prompt. Assistance in using the relax prompt and scripting interface can be accessed by typing 'help' within the prompt. Processor fabric: Uni-processor. Hardware information: Machine: i386 Processor: i386 Endianness: little Total RAM size: ? Mb Total swap size: ? Mb Operating system information: System: Darwin Release: 10.7.0 Version: Darwin Kernel Version 10.7.0: Mon Mar 28 13:34:53 EDT 2011; legacy kernel v7 :xnu-1504.9.37/BUILD/obj/RELEASE_I386 Mac version: 10.6.7 (, , ) i386 Distribution: Full platform string: Darwin-10.7.0-i386-64bit Python information: Architecture: 64bit Python version: 2.6.1 Python branch: tags/r261 Python build: r261:67515, Jun 24 2010 21:47:49 Python compiler: GCC 4.2.1 (Apple Inc. build 5646) Libc version: Python implementation: CPython Python revision: 67515 Python executable: /usr/bin/python2.6 Python flags: sys.flags(debug=0, py3k_warning=0, division_warning=0, division_new=0, inspect=0, interactive=0, optimize=0, dont_write_bytecode=0, no_user_site=0, no_site=0, ignore_environment=0, tabcheck=0, verbose=0, unicode=0, bytes_warning=0) Python float info: sys.floatinfo(max=1.7976931348623157e+308, max_exp=1024, max_10_exp=308, min=2.2250738585072014e-308, min_exp=-1021, min_10_exp=-307, dig=15, mant_dig=53, epsilon=2.2204460492503131e-16, radix=2, rounds=1) Python module path: ['/Users/edward/relax/relax-1.3', '/usr/local/lib/wxPython-unicode-2.8.12.1/lib/python2.6/site-packages', '/usr/local/lib/wxPython-unicode-2.8.12.1/lib/python2.6/site-packages/wx-2.8-mac-unicode', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python26.zip', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/plat-darwin', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/plat-mac', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/plat-mac/lib-scriptpackages', '/System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/lib-tk', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/lib-old', '/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/lib-dynload', '/Library/Python/2.6/site-packages', '/usr/local/lib/wxPython-unicode-2.8.12.1/lib/python2.6', '/System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python/PyObjC', '/System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python/wx-2.8-mac-unicode', '/Users/edward/relax/relax-1.3/extern/scientific_python/darwin'] Python packages (most are optional): Package Installed Version Path minfx True Unknown /Users/edward/relax/relax-1.3/minfx bmrblib True Unknown /Users/edward/relax/relax-1.3/bmrblib numpy True 1.2.1 /System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python/numpy scipy False wxPython True 2.8.12.1 /usr/local/lib/wxPython-unicode-2.8.12.1/lib/python2.6/site-packages/wx-2.8-mac-unicode/wx mpi4py False epydoc False optparse True 1.5.3 /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/optparse.py readline True /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/lib-dynload/readline.so profile True /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/profile.py bz2 True /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/lib-dynload/bz2.so gzip True /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/gzip.py os.devnull True /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/os.pyc Compiled relax C modules: Relaxation curve fitting: True /Users/edward/bin/python2.7 relax -i relax repository checkout Molecular dynamics by NMR data analysis Copyright (C) 2001-2006 Edward d'Auvergne Copyright (C) 2006-2012 the relax development team This is free software which you are welcome to modify and redistribute under the conditions of the GNU General Public License (GPL). This program, including all modules, is licensed under the GPL and comes with absolutely no warranty. For details type 'GPL' within the relax prompt. Assistance in using the relax prompt and scripting interface can be accessed by typing 'help' within the prompt. Processor fabric: Uni-processor. Hardware information: Machine: i386 Processor: i386 Endianness: little Total RAM size: ? Mb Total swap size: ? Mb Operating system information: System: Darwin Release: 10.7.0 Version: Darwin Kernel Version 10.7.0: Mon Mar 28 13:34:53 EDT 2011; legacy kernel v7 :xnu-1504.9.37/BUILD/obj/RELEASE_I386 Mac version: 10.6.7 (, , ) i386 Distribution: Full platform string: Darwin-10.7.0-i386-64bit Python information: Architecture: 64bit Python version: 2.7.2 Python branch: Python build: default, Sep 28 2011 12:00:11 Python compiler: GCC 4.2.1 (Apple Inc. build 5659) Libc version: Python implementation: CPython Python revision: Python executable: /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python Python flags: sys.flags(debug=0, py3k_warning=0, division_warning=0, division_new=0, inspect=0, interactive=0, optimize=0, dont_write_bytecode=0, no_user_site=0, no_site=0, ignore_environment=0, tabcheck=0, verbose=0, unicode=0, bytes_warning=0) Python float info: sys.float_info(max=1.7976931348623157e+308, max_exp=1024, max_10_exp=308, min=2.2250738585072014e-308, min_exp=-1021, min_10_exp=-307, dig=15, mant_dig=53, epsilon=2.220446049250313e-16, radix=2, rounds=1) Python module path: ['/Users/edward/relax/relax-1.3', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/setuptools-0.6c11-py2.7.egg', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/py2app-0.6.3-py2.7.egg', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/macholib-1.4.2-py2.7.egg', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/modulegraph-0.9.1-py2.7.egg', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/altgraph-0.9-py2.7.egg', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python27.zip', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-old', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages', '/Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/wx-2.9.2-osx_cocoa', '/Users/edward/relax/relax-1.3/extern/scientific_python/darwin'] Python packages (most are optional): Package Installed Version Path minfx True Unknown /Users/edward/relax/relax-1.3/minfx bmrblib True Unknown /Users/edward/relax/relax-1.3/bmrblib numpy True 1.6.1 /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/numpy scipy True 0.9.0 /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/scipy wxPython True 2.9.2.4 /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/wx-2.9.2-osx_cocoa/wx mpi4py True 1.2.2 /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/mpi4py epydoc False optparse True 1.5.3 /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/optparse.pyc readline True /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/readline.so profile True /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/profile.pyc bz2 True /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/bz2.so gzip True /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/gzip.pyc os.devnull True /Users/edward/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/os.pyc Compiled relax C modules: Relaxation curve fitting: True