What you need to know is that OpenCanvas 7 doesn't have a direct way to set key presses on your stylus/pen like Paint Tool SAI.



Therefore, we have to use an indirect method.

First and far most, you're going to need the latest wacom drivers as you need to be able to access the Wacom Preferences program. If you don't have it already, you can look for wacom drivers on the official Wacom website: https://www.wacom.com/en/support/product-support/drivers

If you just installed the drivers: Once the installation is successful, you have to restart your computer.

Now before you get to setting the buttons, you first need to know the shortcut key for the action you're trying to do. Open OpenCanvas, then go to Toolbar > Edit > Shortcut Key Setting...




Do you see the shortcut key action you want to use for your buttons? Remember them and now open Wacom Preferences.




Go the Pen tab and you will see the Pen Buttons options below.




First we're going to set the Tail button as the Eyedropper tool in Opencanvas, which is the "i" key. Click on the drop menu and select "Keystroke...". Type "i" under Keys and name the keystroke. After that click "OK".




Repeat for the front button. I have mine set to Hand which is the "H" key.


And now you're done. The buttons on your wacom stylus are now ready to use for OpenCanvas.