adding instruments for chord diagrams?

Is this possible?
It seems there is a relatively nice list in the Setup menu. However, I am missing a 7 string guitar with a low B - and it would be great to be able to add instruments. I do need 8 string guitar and various tunings for Chapman stick. I know it’s not mainstream…

I’m afraid it’s not possible at the moment, but it might be reasonably easy for us to add any guitars you have defined in a given project by way of the Edit Strings and Tunings dialog to the list, so provided you have that instrument in your project, its tuning would appear in the Chord Diagrams submenu. We’ll put our thinking caps on. (In the longer term we do of course plan to make it possible to define your own instruments.)