It turns out you can use the current version of TUI with MacOS X 10.9 (Mavericks) as long as you force it to run in 32-bit mode. To do this, first bring up the Info box for TUI - Go to the folder containing TUI in Finder - Select TUI - Type cmd-I (or select Edit:Get Info) Check "Open in 32-bit mode" Also check the box to prevent App Nap (I'm not yet sure if that matters, but it's probably safest) Future TUI releases will either be preconfigured to run in 32-bit mode or else will include the fix. -- Russell P.S. thanks to Russet and Alaina at APO for help testing this. APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 1322 in the apo35-general archive. You can find APO the archive on http://www.astro.princeton.edu/APO/apo35-general/INDEX.html APO To join/leave the list, send mail to apo35-request@astro.princeton.edu APO To post a message, mail it to apo35-general@astro.princeton.edu APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO