CM_MOUSEWHEEL handler needed in Paramchecklist

I think you need to add a mousewheel handler in this component, which will invalidate the window.  If you make some checkbox settings by program, which are not in view, then scroll up the window with the mouse to bring them into view, the settings made earlier are not present.  I have not investigated whether this problem only occurs on Windows 10, where the mousewheel handling can be configured to be different depending on whether the window has the focus; but it was very annoying until I fixed it with this addition! 

We can confirm that in the next update OnMouseWheel* events will be exposed.