It is possible to make a unit turn around without paying any TU cost for turning. You can do this by clicking to move in a direction you want to face, but then immediately right-clicking to cancel the move. So that's left-click once to select a movement path anywhere in the direction you want to face, then left-click again to confirm the move followed immediately by right-click to cancel. The left and right click should be almost at the same time, with as little gap as you can manage.
This doesn't work for a single click of rotation (i.e. 45 degrees), because in that case the unit will take a step before the move is cancelled. But it does work for any turn larger that that. You can make the unit turn around on the spot without them taking the first step of the move and without paying any time units. (And if you do want to only turn 1 click, you can just turn to face the other direction, then turn back again.)
It doesn't seem to work for 2x2 units. I've only been able to do it for normal size units.
From what I understand, this is likely to be a OXC bug also - but I don't have OXC currently so I haven't checked to confirm.
