Thanks for your reply, prkos. I can't understand why this hasn't been fixed. I was planning to use my drawing to control laser cutting of parts and not being able to size things precisely makes Inkscape not very useful for my purposes. Since Inkscape is used by Ponoko's users, I don't understand why...

I'm trying to size a rectangle, but the size will not stay as I want it. This is using the width and height on the top ribbon, but the values I typechange. I've tried using the lock thing, but no go. The drawing only uses one layer so I doubt it's a layer problem. I've read the basic tutorials, look...