The mouse works perfectly well, including its extra buttons, without the bundled software running and yet for some reason, I now have an icon in the system tray that I can click in order to program what the extra buttons do.
Why on earth does this need to be constantly running in the background? I can think of no reason whatsoever other than that someone somewhere in the design process thought it would look clever or something.
I'm going to uninstall the software. I'm certain the mouse will still work but in the unlikely event that I wanted to change what my extra buttons do, I'd have to reinstall it I guess.