1. Nope, you're committed to a move once you make it. No takebacks. That's what they said when I asked about that exact same thing.

2. That will probably be in. At the very least there will be tooltips.

3. You probably can't. It might be possible to put it in, though. it could get obnoxious if each time you made a move you had to click again to stop your character rotating.

4. Depends on how shields are implemented.

5. It seems like a good idea, but it might be exploitable, like X-tasy pointed out. In any case, in the actual game the flee button won't be a teleport to safety, you'll have to run away a certain distance on the map.