Copy block object (dynamic block)

Please see attached file.
Follow the numbers 01 - 03
Is it possible to copy the red shape allong the path, but using the end grips of the green line?
Basicly when you strech the green line, the red object will get copied along the path for a given distance.
Then if you shorten the green line, the red object will reduced.
I now I can get around using copy along curve, but this way the object remain interactive when streching the green line.
This would be something like dynamic block in autocad.

How do you upload a .3dm file here?!

Use this icon in the box you type your message in:

Screen Shot 2022-03-02 at 9.06.02 AM

Or just drag and drop the file into that same box.