Hi huanle5062,
Sorry that you encounter some trouble. Thanks for pointing it out, and yes, it is the battle between compatibility with training material and the progress of the application.
Since more and more functionality is implemented, things had to be moved and structured in a more workflow friendly way. This is not done to change for the change. It is often a more extended discussion. However, it is not pleasant to run into this, I certainly understand. Thanks for pointing it out in such a neutral and professional way.
If you run into this, please try the Commander. You get this Holding down the Shift key, and while holding down press as well as the c key. Now you get an input field that lets you type in what you need. Click on the right suggestions.
More about this:
https://help.maxon.net/us/index.html#50270
I went one time through the content, and it has only a few of those “stopper” in it. Here is the list that I found regarding R21 or S22.
Connect -> Object Manger> Object>“Connect Objects+Delete”
Reverse -> Spline> Point Order> Reverse Sequence
Set First Point -> Spline> Point Order> Set First Point
Extrude (S22) It will use the Spline Axis to offset, it has only one value now by default, but you can access the old and more features in the pulldown Direction.
The camera now has its own menu, it is no longer in the Light icon menu.
Again, thanks for pointing this out and enjoy your explorations here.
Cheers, stay safe, stay healthy.