Thanks to @JerryAshton and google - here are the steps:
Open Onsong and press the gear in the top right corner
Editors => Actions => Screen Triggers (Click “screen” on the bottom) => Click the area you want
New menu pops up and Midi → Events => Send
Then @JerryAshton directions work
- button => Go to “Contol” and then
Hope this helps somebody else or I’ll just use it when I forget!