Maybe this will help:
This book I would recommend for self-learning the more complex development techniques within filemaker.
As they say "there is more than one way to skin a cat."
You could also use conditional formating by setting the colour of the screen elements you wish to hide the same as the background colour and apply a script trigger so that on object enter, if the condition is not met, move to next field.
Hope this helps
Thanks very much for the advice. I'll get a copy of the book and try it out. Also thanks for the tips on emulating the Notes conditional field display function.
This file, by John Mark Osborne, at databasepros.com, shows what is called the Visibility trick. It involves using a relationship which is either valid or not. When it is not, nothing depending on it is there. A portal based on it will hide all its contents; incl. fields, text, buttons, whatever. The relationship typically targets a "constant" field (which is the opposite of the way we normally use constants).
The link below will take you to the page with the file, in this window.