It is possible to run multiple copies of the same Chimera on a Mac. Here’s how. From a Terminal (/Applications/Utilities/Terminal) type the command open -n -a Chimera The -n option tells the Mac to start another copy of the application. If you prefer to start the second copy by clicking an icon then you can make that icon using /Applications/Automator, choose to make an Application, select Run Shell Script, enter the command open -n -a Chimera as the script to run, then File / Save… to save this application as “Chimera+” or whatever you want to call it. This icon always starts a new copy of Chimera so you can have as many running as you like. Tom