Currently using DisplayFusion Pro v3.1.5 (Registered User), on Windows Server 2008. Loving it for multi-monitor taskbar and wallpapers.

I often have scrollbars close to the taskbar, and while I'm dragging back and forth (scrubbing), my mouse might drift down towards the DisplayFusion taskbar.

If, while the button is still down, my mouse sits over taskbar entry for more than a few moments, DisplayFusion will focus that application.
The standard Explorer taskbar does NOT do this, only the DisplayFusion one.

Is it possible for you not to send focus to an application unless I actually click the entry?

I'm guessing this behaviour is because you're replicating the 'drag object to item on taskbar - hover to focus' type behaviour from Explorer.

Steps to replicate:
- Run several applications, atleast one with with horizontal scrollbars
- Position apps on a screen with DisplayFusion taskbar
- Click and drag back and forth on Horizontal Scrollbar in App.
- While continuing the horizontal drag, allow the mouse to drift down to taskbar entry for another application.
- Focus will change to the other application.

Yes, I really should be more accurate with my mousing -- but this is a regular occurance for me, with applications with minimal (10-15px) chrome - I'd need to be almost robotic to not trigger it.