Hi there
I'm no expert but am doing a module on radio scripts at the moment for my writing course. For script layout, you may find it useful to look at
http://www.bbc.co.uk/writersroom/insight/scriptsmart_formats.shtmlYou can download Scriptsmart on the site as well, which is formatted for writing scripts and also read scripts from plays and dramas to get a feel for how it's done.
The main difference between a short story and a radio play, though, is that pretty much everything has to be conveyed via dialogue and to some extent, sound effects.
If it's a script for the stage or TV, then you can, of course, convey things through actions as well.
I've found the BBC site really helpful and have read some great plays as a result.
Good luck
I hope this helps
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