Hi all,
Windows Vista and OS X 10.8 (Mountain Lion) are no longer supported officially by current and future versions of PixInsight. The PixInsight Core application should still run on Vista (with Service Pack 2 installed) and OS X 10.8, but we no longer test it on these operating system versions, so we cannot guarantee that it will work correctly.
I have just updated the System Requirements page to reflect these changes (you may need to refresh your browser):
http://pixinsight.com/sysreq/
