Testator
They are called screenwriters, or just writer.
A male writer is called a poet so maybe a female writer is called a poetress
An autobiography writer is called an autobiographer.
A writer of literary works is called an author or a novelist.
The text of an opera is called the libretto and the writer is called a librettist.
A person who writes comics is typically called a comic book writer, or simply a writer in the comic industry.
A male is an author and the female is an authist
A writer's collected works are often called a "bibliography" or a "collected works".
Its called a writer.
composer
A cruciverbalist.
A bad writer is called a Hack