>I would like to have the user enter the parent and then as many child records as required before exiting the form, and also be able to get to an existing parent and add/edit as many child records as needed.

Two suggestions from me!

One would be to have the data in a page frame. Page one contains the parent and automatically links to page two. Page two contains the child and repeats.

Second would be to have a grid containing the child records - I believe you can allow adding of rows to a grid.