Above my pay grade.

This should be simple in FF. I noticed there was a "data backbutton" Problem is for me with all of these attributes I don't know what they do or how to use them plus the aria stuff. Where is all of this hidden?

This does look like it is simple in Foundation. The attributes are put in right below the elements in the design panel.
Search for the attribute data-multiple-opened and add it. Then set the data attribute to "true".
You can even add custom data attributes.
Just make sure you add the attribute and value to the correct class as in the jsfiddle example.

My aha moment a few months ago was to open my exported index file (and others) in Coffeecup HTML editor and I started to see what the relationship was between the cool settings Coffeecup Responsive software was performing and how that translates to a web page. Once you upoad your page, start using the inspector in Firefox or Chrome to see the code "live". Really eye opening stuff !

I have finally figure this out. This is so simple!
On the nested (2nd, 3rd, 4th.....) modal window that is to open, click on its "close button" so Inspector can find correct button. Next click on Design icon. Under Attributes open Aria Label delete value. Then delete Data Close attribute and add Data Open. Set Data Open value to equal the name given to Modal Window 1.
Now instead of modal window i and 2nd modal window closing the Close button will send you back to modal window 1 being able to click on other buttons. This is needed for multiple nested buttons.
Hope this helps someone else.

Looks like there are two ways to do it.
Thanks

Cool, I'm glad you guys and gals are picking up on some of this. I was going to chime in again if you had issues but I knew you could get it if you looked at the simple example. I know it doesn't look so simple when you look at it the first time but if you only look for what's different it gets a little less fuzzy.

Thanks Eric, We APPRECIATE all your support !