On Windows. After selecting a run of text it would be nice to change the cursor from the edit bar | to something that indicates drag and drop is possible.
There is no standard cursor or affordance of this type that I'm aware of; I would caution that supplying a custom cursor that doesn't look terrible on at least some platforms would be a task you really need a graphic designer for.
Not critical. We can handle in documentation. Can the gear icon be reduced in size slightly?
The icon itself can be shrunk to any size (or I can find a smaller icon). The window chrome is another story; I am aware that it's pretty big on Windows while on OS X it's more reasonable. I don't know how much we can control this, but I will look into it.