machine shipped yesterday, yea. so I have been playing around with the edu software. making some progress [a little] .. I have a simple part drawn up and want to add a cutout /slot to the bottom . but when i choose the square tool and drag it over to make a rectangle the size I want, it wont stay on the screen I right click and the edit guides come up, delete those and my rectangle disappears , left click does nothing. I am missing a step here