I was a little confused by this too; but once you’ve saved the widget and if the code doesn’t show within the widget (below the checkbox for Auto fire on Page Load) then I would suggest refreshing the Widget page again and you should see a line of text that looks like this:
<a href='#' data-reveal-id='text-2'>Open this popup</a>
which you can copy and paste into your content.
The problem is that the text does not show entirely on my resolution screen – it’s cut at the end.
See here: http://tof.canardpc.com/view/ebdd92b1-8c52-499a-aaba-da6f603eb2e3.jpg
I suppose one temporary way around it would be to View Source and look for the code; at least that’s how I recall doing it 🙂
Long term though – perhaps the text can be displayed in an input ‘form’ or clicking on the text selects the whole thing allowing the user to Ctrl-C etc.?
If it’s any help, I noticed that this functionality is available through Contact Form 7 when copying the short code.
I’m sure the developer will come up with something ^^
Well, as I don’t have the use for the moment, I will wait for an eventual correction.