Due to the recent release of macOS Sierra, it has come to our attention that some Mac users may experience a problem connecting to DM or Pro Cloud. We recommend upgrading to the latest version of the Citrix Receiver (12.3) to resolve the problem entirely. Simply follow this link here
Once you download the file, open and run the UNINSTALL, once that is complete, then run the INSTALL.
Desktop Shortcut Users: For any users that use a desktop shortcut to access Design Manager, please follow the instructions included here
If you are having any problems getting the new receiver installed properly, please contact our support team.