Best tracking: during setup, size the two windows to a similar shape & size — the closer they match, the tighter the blue line tracks.
Reset to line: stops both screens on the same line at the blue guide — use it to re-sync after a jump.
Play / pause: Spacebar. Arrows = faster / slower.
Bold / italic / highlight: select text, hit B I H
Move the blue reading line: drag the handle on it.
Jump around the script: drag or scroll-wheel on the text.
Connection blips: it reconnects itself. The script and place are kept.
Lock control (producer): talent goes read-only until you unlock.