I want all fields to rely on the same display rule, but when I use a display rule for the email address field, it wipes out both Email drop down auto response choices in Settings >>Email Notices (Reply-To and To).

Rather than just the first field showing, I now have to have the email address showing or else forfeit any email notifications on both the company and user's part.

http://www.southcoastflagpoles.co.uk/template-tables2.htm

The attached info.fb has the display rule on so you can toggle it off to see the difference. The test link above does not have the display rule.

How can this be fixed?

That is correct, Anything with a conditional has to be showing at submit to be received. They're work arounds.
Explain a little better and I maybe able to help you with that.

On the Southcoast link above, it shows the second question as the email address, but I want it hidden and only to drop open with the rest of the questions after Single or Double Sided is chosen. All other questions I have used a display rule, but when I use one for the email address question, the Email Notices tab in Settings has no drop down options to choose [email] and is simply empty. If I change the email question's properties to Show Element: Always, then inside of Settings>>Email Notices, the drop downs do hold the email address as choices.

Attached was an fb file to install to change the properties of Show Element and then to go look at what happens in Settings Email Notices (Reply To) and (To).

Two printscreens may help. See attached.

Email addresses that are hidden and part of a display rule cannot be selected under email notices. They must be always visible.

I also see you are still on 2.4 so you might want to upgrade to version 2.5 as well.

"They must be always visible"
Why?

Because that is how the software works.

Check this thread out.
http://www.coffeecup.com/forums/web-for … ialog-box/