Deprecated use thing:1766370 instead

Stopper for roomba to prefent it from going over a low doorstep. If there is any interest I might make an adjustable version

Yes

I haven't printed it myself but used shapeways. Should be possible though. They have been lasting for more than two years now.

You can use the original screws. Pay attention where you place the stoppers. There are only a few places where they don't get in the way of the brush or hinder the front from moving freely and don't get in the way when docking.