The ability for Banktivity to open your Document (data) file automatically when launching the Banktivity application relies on the Recent Items setting in System Preferences on your Mac.  Go to > System Preferences, then click’General’, look for the setting entered with:

Recent items ____ Documents, Apps, and Servers

This setting will need to be set to one of the numerical options (10 is the default).  If the Recent Items setting is set to ‘None’, Banktivity will not automatically open your Document (data) file when the Banktivity application is launched.  After adjusting the Recent Items setting in System Preferences you will need to open your Banktivity Document (data) file manually once more, then in the future your data should open automatically when the application is launched.

Note:  There have been reports of the Recent Items setting reverting to ‘None’ again after changing the setting to one of the numerical values when using OS X 10.11, El Capitan.  Typically restarting the Mac resolves this issue. If you continue to experience issues with Recent Items reverting to ‘None’ please contact Apple support.