My Now Time has disappeared and the track view no longer scrolls

"pause/break" key....   (or scroll lock key)

Have you tried a bigger hammer?
 
 
 
 
 
 
Sorry,  I got nothing else..

Note that there are two independent scroll-locking functions - left/right click locks scroll (set in Track View Options menu), and the Scroll Lock key on your keyboard. Whichever one has been enabled needs to be disabled the same way - i.e. click in an empty area of the clips pane or hit the Scroll Lock button again. It's possible to have both enabled, and have to undo both to get scrolling back.
 
Incidentally, pause/break enables the so-called CPU Conservation Mode that reduces the screen update frequency to approx. once/second, making the Now time jump in increments. But the view will still scroll when the Now time reaches the end of the window.