For your first question, can you provide a bit more information? Using a specified label in the Axis settings can be one way, but the easiest solution depends on the command are you using, and whether these are text labels or numbers. If you can upload a screenshot, that can also be helpful.
For your second question, a video sounds like an excellent idea for the Rainbow Plots. We will do more videos this fall on YouTube and have added this to our list!
In the meantime, one thing that might help is you can hover over a command, and a pop-up will tell you the command. For example, sideways histograms are created using the Box command, a command that has a lot of drawing options that go well beyond box plots.