You shouldn't have any problem. I run multiple versions of oxygen because of different user requirements at my company. Shouldn't be any different when using 2 of the same version. I name each root folder for the version and have complete copies of oxygen and then have different startup icons for each. Tricky part is detecting which version is running. It seems like most of the time I can only have one oxygen session running at a time, but once in awhile two seem to start. This will catch me when I have oxygen in the background on the Mac and I click on the icon to start a specific version. The backgrounded version will come forward instead of the one. In my case I can use the About screen to verify the version. Hopefully with the customized version there is something detectible in a top level menu.  ..dan Sent from my T-Mobile 4G LTE Device -------- Original message -------- From: Kristen James Eberlein <kris@eberleinconsulting.com> Date: 7/2/18 6:00 AM (GMT-08:00) To: oxygen-user@oxygenxml.com Subject: [oXygen-user] Suggestions for having multiple instances of oXygen 20.1 on a single system Hi, guys. I could use a suggestion. I have oXygen 20.1 installed as my primary company XML editor, but now a customer has upgraded also to oXygen 20.1. Their installation is quite configured -- toolbars, options, a CCMS authoring bridge. Any suggestions for having two instances of oXygen 20.1 installed and functioning on the same laptop? -- Best, Kris Kristen James Eberlein Chair, OASIS DITA Technical Committee Principal consultant, Eberlein Consulting www.eberleinconsulting.com +1 919 622-1501; kriseberlein (skype)