Dear all,
I don't know whether this is already well established knowledge and I am not sure if this works in every case but here is what I stumbled upon:
Picture the following scenario:
You just passed a carefully adjusted waypoint (TWA/HDG). However, you change your mind and adjust the course by hand. Then it strikes you that the last step was a big mistake and you want your carefully chosen waypoint back--here's what you do:
1. Open the waypoint menu.
2. Select the next waypoint tile which activates the course selection for that next step in time.
3. (Without any further clicking around) close the waypoint menu by clicking the x in its top right corner. You will be prompted whether you really want to dismiss without changes. Confirm this *by clicking the red tile with the x*!
4. Now reopen the waypoint menu--voilà, here it is again, your waypoint tile from the past.
5. Select it and simply move it to the future ("minute up" or "hour up", either will work). It's good to be used again.
In fact, I think this exact mechanism is responsible for at least a part of the cases when people experienced that their ship turned around by 180° when they (unwillingly and unknowingly) pursued the same scheme with the actual waypoint menu (not the TWA/HDG version but instead the coordinate version): They opened their waypoint menu just after having passed a waypoint without having programed any other waypoints and closed it the way I just explained which raises the passed waypoint from the dead...without being displayed in the chart!
Cheers,
jokap