Mac OS X, 10.12.5, SketchUp 17.2.2554
In going through the SketchUp tutorials, I’ve come across a problem.
See: Third introductory video at about 7:00 minutes.
You’re directed to create a window mullion of 1/2". If you use the Offset tool with a mouse controlling how much offset, it works properly. If, however, you type 1/2" into the measurement box, the mullion extends out instead of in.