This will be the text on your button.
You can add an url, or pick from the given link options, where you can find lightbox or slide switching options. Also you can choose if you want to open up your link in a new page (Target -> Blank) or in the current one (Target -> Self). And there are rel attribute options too.
Your button can be either as wide as your text needs it to be, or with this option it can be as wide as the layer is.
If it's turned on, and your text is longer, than the width of your layer, it will still stay in one row. If it's turned off, the text will go to the next rows.
Custom CSS class Expert
You can add a custom css class, that will be applied to the button layer.