To Remap a Button

Do one of the following:

In the Button Assignments dialog ( File > Settings > User > Button Assignments ), click Remap Buttons.

or
In the Digitizing dialog ( File > Settings > System (PC) > Digitizing ), select Tablet > Button Assignment.

The Button Mappings dialog opens.
In the list box, select the logical button whose mapping you want to change.
Put your pointer in the Button Definition Area below the list box where the instructions appear.
Press the physical button (or mouse button combination) that you want to map to the selected logical button.
The new button mapping appears in the list box.
Click OK.
(Optional) If the Button Assignments dialog is open, click Save.