I know how to make a rectangular region on a given layer and assign it a net. However, I can also make some arbitrary polygonal shapes using the tools. However, I don't see how to make shapes that have holes in them. I don't care if the holes are round or square. I'm just trying to create a solid rectangular region that dodges a few vias but is otherwise continuous and is all assigned to a particular net. I can build one with several rectangles, but then all the rectangles are separate and electrically not connected. Is there a way to create one big rectangle and then cut holes in it?