problems selecting items in list boxes ( i.e. genre list box in musician search)

[StuartR]

You do not mention
a. if you were previously able to select them?
b. where you are making the genre selection since it is located both your on JK profile settings and of course when creating or scheduling a session.
I use Sierra with 2012 MB.I don't think what you're experiencing is related to Hardware or OS.

Out of box questions.
1. you using the trackpad or external mouse?
2. you're able to click around on other JK checkboxes and list?

In other words, we need more information