Bug - CSS Button Module

According to http://scriptcase.net/blog/creating-…strap-classes/ , I tried to create a new CSS Button under the public
When i click Next at the bottom, I brought me to a button management screen and there is a Name field to enter, I did not enter a name and click on Save button instead of Cancel, and a message pop-up saying name cannot be blank, I close the message and it keep popping up and does not allow me to cancel or enter a name in the field.
The only way was to close the entire browser tab.

After that, I re-login to scriptcase v8.1 and enter into my project, and I click on the CSS button module and the system just stuck at the Loading prompt.

How to resolve this issue?

What browser are you using?