After going to the "Edit buttons" window and saving again, it looks good. I repeated the process by adding Twitter account, and had the same issue – spinning indicator, but after opening "Edit" window and saving again, it worked.
Also, would it be easy to sort icons by social networks popularity rather than name? Most users more likely be looking for fb, twitter and instagram, rather then digg or odnoklassniki, so it makes sense to put most popular on top. Plus it's not really obvious that the order is alphabetical just by looking at icons 🙂
And thanks for the terrific plugin!