This example shows a laptop with one built-in display plus two connected external monitors.
If the operating system recognizes such display, ShareMouse also recognizes and counts it as a separate display for each computer. if you have a monitor switch, that can switch a single monitor for use with multiple computers).
ShareMouse does not know if you really don't use it or if you just claim not using it.
If you purchased the Standard Edition by accident recently, you can upgrade your license from Standard to Pro.
If any computer has more than one display, you would need the Pro Edition. This is a laptop with one integrated display plus an additional monitor (aka "display") connected to that laptop.