rma

Sorry to post on such an old quote, but I experienced the same thing with a recent download of Paint.net and found the solution. I didn't see this in other posts on this forum, so I thought it might be valuable to others. It first appeared to me like the fixed size selection was not working. I played around with it quite a while. then I realized that my image size was smaller than I thought. Therefore, my fixed selection area was mostly outside the range of the canvase altogether. I would drag it around, and it would appear to expand and contract from the lower right corner. When I increased my image size, I realized it was working properly. Note, you do have to click and start dragging for the fixed rectangular selection area to appear. However, it does not resize unless you move part of the rectangle outside to boundaries of your canvass (and then it only selects a portion of your rectangle- i.e., a smaller size). I actually wanted to make rectangles of specific sizes. I successfully accomplished this by using the rectangle select tool, then setting my dimensions and color, then hit Backspace key (to fill the selection with the current color), then change to the Pixel Move tool and use the arrows to move the rectangle to the desired spot. Not very intuitive for me, coming from Adobe's tools. Still, once you get beyond that learning curve, it's pretty effective.