cancel last order

Every strategy game has this problem: You queue up a hundred orders in a row, then accidentally miss the next target and wind up giving a movement order instead. So now your ship is going to attack a few things, move to some arbitrary location, and then do whatever else you asked it to.  Or else you can cancel all the orders and start fresh, hopefully by some miracle not making the same mistake again.  This isn't SUCH a big deal in most games, but SoaSE has such a grand scale that you're usually trying to click on things you need a microscope to see. (not complaining)

Supcom solved th is by giving you a special command to adjust your orders IIRC, but just a way of cancelling the last one would do the trick. Is there a way to do this that I haven't found?

Also it's damn irritating that the one thing EVERY RTS game has - the ability to cancel a construction order by right clicking - is missing here. What gives? Right clicking serves no other function during construction if I remember correctly, so why ignore this basic tenet of RTS interface design? I think hitting ESC has the same effect but having to reach for the keyboard slows you down, it's unnecessary.