This is an update on my previous comment about being able to get scroll to work on my desktop, but not on my laptop:
I was able to get scroll working on my laptop too, but NOT by going to X-mouse settings and unchecking Make scroll wheel scroll window under cursor like I had previously done on my desktop.
On my laptop I instead found that if I go into Windows settings>Mouse and turned on Scroll inactive windows when I hover over them, that mouse wheel scrolling works.
As an experiment on my desktop, I tried re-checking Make scroll wheel scroll window under cursor in X-mouse and turning Scroll inactive windows when I hover over them in Windows settings on and off**.**
Scroll didn't work on either setting.
So on the desktop it was a setting in X-mouse and on the laptop it was a Windows mouse setting. Why they're different I have no idea.
Hope that helps.