The more I find out about LaTeX the more I realize that 90% of LaTeX is cheap hacks. In that vein, I offer the following solutions to your queries.
With regard the the numbered scenes, I would use the following tag "\section{insert scene title here}". This will automatically number the scenes and will give them the title that you put in. For interludes, you might simply want to use "\section*{insert interlude title here}". All the asterik does is tell latex not to number that particular section so that it doesn't throw off your scene numbering. I am not entirely sure how to get seperate numbering for interludes if that is what your heart is really set on. You would need to talk to someone 1337 like Vrable or Erika for that. (Or it might just be really simple and I don't know about it. Who knows?)
The best way that I know of to have columns is to use a table and just put the stuff in the table and let latex figure out the spacing for you. An LJ comment is not nearly enough space to try to explain LaTeX style tables, so I will let you look them up online. However, if you want a few samples, let me know.
As for the centered and italicized stage directions, I am not entirely sure what you mean by "centered". Everything in LaTeX is by default "justified" to it evenly goes from one side of the page to the other. You might try "\begin{center} insert lots of stuff to be centered \end{center}". I am not entirely sure what that will do for something that is already spanning the width of the page though. As for italics, there are two options: "\emph{stuff to be italicized}" and "{\itshape stuff to be italicized}". Sometimes one works, sometimes they both work. I don't really understand it.
As for the using the whole sheet of paper, there is a really spiffy module that someone wrote for that. Just type "\usepackage{fullpage}". If that doesn't work its because either you don't have the package or because latex is looking in the wrong place for it. If you experience these sorts of problems let me know and I will see what I can do from afar.
Anyway, I think that's about it. This is turning into somewhat of a tome but I know how hard it is to learn latex. It has quite a learning curve over MS Word, but I think that once you figure out all its little foilbles it is better for quite a few things.
no subject
With regard the the numbered scenes, I would use the following tag "\section{insert scene title here}". This will automatically number the scenes and will give them the title that you put in. For interludes, you might simply want to use "\section*{insert interlude title here}". All the asterik does is tell latex not to number that particular section so that it doesn't throw off your scene numbering. I am not entirely sure how to get seperate numbering for interludes if that is what your heart is really set on. You would need to talk to someone 1337 like Vrable or Erika for that. (Or it might just be really simple and I don't know about it. Who knows?)
The best way that I know of to have columns is to use a table and just put the stuff in the table and let latex figure out the spacing for you. An LJ comment is not nearly enough space to try to explain LaTeX style tables, so I will let you look them up online. However, if you want a few samples, let me know.
As for the centered and italicized stage directions, I am not entirely sure what you mean by "centered". Everything in LaTeX is by default "justified" to it evenly goes from one side of the page to the other. You might try "\begin{center} insert lots of stuff to be centered \end{center}". I am not entirely sure what that will do for something that is already spanning the width of the page though. As for italics, there are two options: "\emph{stuff to be italicized}" and "{\itshape stuff to be italicized}". Sometimes one works, sometimes they both work. I don't really understand it.
As for the using the whole sheet of paper, there is a really spiffy module that someone wrote for that. Just type "\usepackage{fullpage}". If that doesn't work its because either you don't have the package or because latex is looking in the wrong place for it. If you experience these sorts of problems let me know and I will see what I can do from afar.
Anyway, I think that's about it. This is turning into somewhat of a tome but I know how hard it is to learn latex. It has quite a learning curve over MS Word, but I think that once you figure out all its little foilbles it is better for quite a few things.