This has been lying in a cupboard for 15 years since I wrote it in 1995. It was the first large app I'd ever written for the Atari. It's coded in Turbo Basic, but a 31K compiled version is also supplied.

http://www.atari8.co.uk/

There's no manual, but the program is pretty easy to use. I wanted to share it after all these years, having just discovered it again.