sucks on the api restrictions, but can't do much about that.
Control click sounds fine to me, I just wouldn't remove clicking the '1' as that seems a little more intuitive to use and a convention in a couple places.
... for the control click, is it going to navigate back to '1' or go in reverse order? I assume back to '1' but I can see it going either way.
UX wise I would tend to not use any right click anything on map operations because right click in the zoomed out radar map brings up a new tag modal dialog. (unless that's fixable)
Introducing the time delays I can definitely see the desire to edit the last placed and extending from that, being able to undo the last placed.
for '+', '-', button to increase time ... .... how about instead of a button (or as well) clicking an already existing waypoint brings up a modal that you can type in the time or possibly remove the waypoint if desired.....