how can I unlink the project and lower zone cursors and zoom? I can’t find out in the manual, it says if you activate this feature but doesn’t say how. 
In the lower zone, click the little gear icon in the upper right and make sure Auto-Scroll is checked. Then there should be an icon along the top of the lower zone that looks like a chain link. This icon controls whether the cursors (and zoom) in the project zone and lower zone are linked.