Hi entry-newspaper,
Enjoy the introduction. Please know that it is just the very basic of it. It needs time and practice, so please allow time to sink in.
Quoting (freely) my friend Noseman to use Scene Nodes – a very good and deep knowledge of the options that can be done in the Object Manager is required.
It might be preferable if it can be done in a non-Node mode.
I haven't counted the Scene Nodes, but it is worth reviewing the manual.
In summary, this is far from intuitive. From my point of view, those are technical director options that are less designed for artists (regarding intuitive use).
I have not decided how far I can support this, as some questions might require days of construction, going by solutions from Rocket Lasso, for example. My ideal would be an extra forum even. Which I will discuss hopefully next week when we are all meeting to exchange ideas.
About your second question.
Press play for the file below to shape something and have a perfect Spline drawing. Adjust the Keys in the F-Curve accordingly. I have looked at the time, so selecting the two inner or outer keys allows you to change those (up or down)
CV4_2025_25_MOcs_01.c4d
When the shape is right, use the Current State To Object to get the Spline as an object. This is the fastest way I can think of, and I have explored several methods during the past hours.
The playhead stops because I have set it to run only once. To start over, it needs to be set to frame zero.

Cheers