I have added a hero slider in my WordPress site using the slider revolution. However I couldn’t add/edit button link using the “Actions” window. The Actions popup window seems freeze within Slider Revolution plugin. Can someone explains me why is this? Is this because I need to buy the premium version of Slider Revolution to give a button link? I have attached a screen shot of this. Please advise. Thanks.

I have tried created a new slider. Same happened. Cannot give a button link using the Actions.