Use of your electronic laser was no better than my using a tape measure. After using the laser at least 5 times to repeat accuracy of measurement, the window is about 1/16" too tall. As a result the window has a slight bow to it. It is acceptable, but my tape measure was more accurate. Also, there should be D rings in each of the 4 corners. Per your video you push the window into the frame. I have blinds mounted at the top so the window needs to be inserted from behind the mounting brackets and pull forward. The company was kind enough to send me extra D rings and instructions. Thank you.