If you want to use the software which came with your mouse, you will need to run it as an administrator.

If you want IS Boxer to use your mouse, you will want to not be running the Set Point software.

Create a keymap for whatever.
Click the arrow to the right of the hotkey window.
This opens up the window, where you can push whatever key and select modifier keys.
From here, I can use mouse buttons (forward thumb button for example, comes up as Mouse 5).
Even if it doesn't recognize what you want to push, you can hit the arrow and scroll down until you see Mouse 5, or whatever button you want; my options are Mouse 1 through Mouse 8, and Scroll Wheel Up + Scroll Wheel Down.