Help. Change instrument worked ONCE then never again!

Doesn't matter how mamy times I click nothing happens, playing, not playing, restarted new song, etc etc nothing works!

At a loss...

Just to make sure I uninstalled and reinstalled as admin, no change.

The tooltip works talking about dragging to midi or& the name of the instrument

Figured It out. It's a matter of WHICH instrument name of the track you click on. the manual doesn't make it clear

that it's the vertical one next to the slider. thanks for looking...