Hi there DMC,
An indicator in itself does nothing (but you could set alarms on it). It would require a piece of code for AutoTrading (see the button under the mouse arrow below how to get there), and this code will ask for the Indicator’s status and depending on that do something. You talk about a Trailing Stop which is fine, but you’d first need to take a position – and this has to be done by the AutoTrading system just the same. It is thus NOT so that you can open a position manually, and let an Indicator signal close the position.
What you see below is the bottom of a chart and the button under the mouse arrow can be larger as well (but carries the same icon).
Maybe it is a good idea to look for instruction videos on ProRealTime. Quite many exist. Look (Google) for
ProRealTime instruction video
and you will find many.
Have fun !
Peter