Two Mac binary installers are currently available:
If you want to run IMP on a different type of Mac (e.g. a PowerPC system) you will have to rebuild it from source.
Please check the installer package against the MD5SUM file to make sure it has not been tampered with (open a Terminal window, change into the directory where you downloaded the .dmg file, run "md5 foo.dmg" where foo.dmg is the name of the file you downloaded, and compare the output to the content of the MD5SUM file.)
The MD5SUM file in turn is signed with this GPG key; you can check to make sure this has also not been tampered with using the GnuPG software.
The installer will install IMP in the /usr/local/ directory on your Mac.
The IMP Python libraries are automatically set up to run with the default version of Python on your Mac. To run an IMP Python script called foo.py, simply run python foo.py from a Terminal window in the directory containing the script. (If you have multiple versions of Python installed on your system, you may need to force use of the default system version by typing /usr/bin/python rather than just python.)
Note that the IMP Mac package does not currently include the 'foxs' command line tool for small angle X-ray (SAXS) fitting. This will be remedied in a future IMP release. For now, please use the web interface or install IMP on a Linux machine.