you can use the MITER command to round corners. I hope this is what you asked for....
Concerning your 2nd question: As soon as a track is connected to a pad you can't simply move it to another pad. You have to draw a new track at the other pad with the ROUTE command.
In case you draw the layout without a schematic in the background, you could use GROUPT/CUT/PASTE for duplicating wires/tracks. But in the case the wire/signal name will change.
