Simple gravity simulator in Visual Basic

I wrote a program in Visual Basic that simulates gravity. Basically, it just simulates a box falling. Not that interesting, but the point is you can look at my code and see how I did it. As you can see from the screenshot, it has two modes: manual step, where you can click the Step button to advance one frame, and automatic, where it runs the simulation in realtime. You can also turn off the gravity, which basically just disables acceleration. The scale is one inch to one meter.

(Now to get some sleep...)

EDIT: I really was tired. I forgot to post the download link! Sorry about that... :-/
Here it is: http://www.mediafire.com/?jzamowkogdd