Help with using Draw

Hello,

First of all, I would like to thank the developers for releasing a stable beta version of TeXmacs. I have had no issues using it on a Mac M1—great work!

Now, to my question. I must admit that I am quite confused about which keys to use when running TeXmacs on a Mac.

In the YouTube video “Drawing a Simple Geometric Picture with TeXmacs” (timestamp 2:11-2:18), the figure was moved up and down. However, I am not sure how this was achieved. What keys should be pressed on a Mac? Is it just the down arrow key?

Additionally, I didn’t understand which keys were used to move the first parallelogram on the left to the back, making the edge in the front visible.

Is there any specific key or combination to select an edge or a face?

Apologies if my questions seem a bit naive.

Many thanks,

Ed