FCP 7 Multi-Cam Video Edit

I posted earlier with this issue but thought I would update the title since this seems to be an issue when working with multi-cams.

Here is the issue:

We have to edit camera angles left center and right. If we mess up an edit and want to re-join the media we cannot get it to work except on the first initial cut. Also we are only cutting video the audio is always through the left camera. How can we go back and make multiple edits if need be?