Gumball: how is it supposed to work in OSX version?

I’m completely new to Rhino and might be completely wrong about this. Having seen gumball in action at YouTube I gave it a try.

A: To move a surface I’ll just drag one of the axis arrows, works great.
B: To move a distance I’ll enter a number and press enter, works great.
C: To create a solid out of a surface I’ll hold down Cmd-key (not ctrl as on Windows), works great.

D: But, how do I create a solid with a thickness of an entered number?
First try: Drag arrow, enter number, press Cmd, release mouse -> suprisingly, this seems to be the same as ©
Second try: Drag arrow, enter number, press Cmd, press Enter -> nothing happens


There is no “make a solid” gesture.
Perhaps what you mean is offsetting a copy?
If so:
1 Select the object
2 Click and hold on one of the square scaling Gumball boxes
3 Tap Alt to copy (look for the little “+” glyph
4 Press and hold Shift
5 Drag out the copy to the new size

The Help file has lots of good detail for Gumball and other Rhino commands