You may assign different values or results to the mouse actions by using the KEYSTROKE configuration variable. This variable is described in detail in The KEYSTROKE Variable.
For example, to cause the right button to delete the current character, use the following configuration entry:
KEYSTROKE Edit=Delete Mr
The Edit=Delete phrase indicates the desired action; the Mr phrase is the key code associated with the user's pressing the right mouse button. You may also accomplish the same thing in COBOL by using the SET ENVIRONMENT verb:
SET ENVIRONMENT "KEYSTROKE" TO "Edit=Delete Mr"