Unable To Install Revolution Plugin Slider .zip Files

I am very new to all this. I have installed a new theme, and plugin for Revolution Sliders. I am trying to load the demo sliders, so I can see what I like, and try to use them in my site. However, when I try to load them, I receive the following:

importing slider settings and data…
Error: Import file not found!!!
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I have searched the forums. I un-zipped the file to check, and the contents look complete and uncorrupted. I have downloaded them at least twice.

I communicated with support at the vendor of the theme and he tried to install the sliders, but could not either. He asked me to check if there was a “zip extracting module” installed and turned on.

I thought I had installed either the theme or plugin using a .zip file, but I’ve been at this for so many hours, I am no longer sure.

Thank you for any assistance.