how I can enter screenwriting mode?

I’ve looked around, but could not find a way…



In the Text menu, it is at the very top under Modes.

My text menu has “highlight”, “annotation”, “footnote” at the top… I’m using version 1.0m RC b1

It’s new in b2.

Yep, as cruxdestruct has already pointed out, you will need to download the most recent beta (beta 2) in order to enter screenwriting mode - it didn’t exist in beta 1.
All the best,