Actually IT HAS TO DO WITH YOUR THEME. I’ve tried with and without images.
Please read (this is taken from your site, I followed this instructions and it doesn’t work):
Demo Content
NOTE: before importing the demo content, make sure you have installed & activated “Revolution Slider” and “Contact Form 7” from within Appearance > Install Plugins, and also installed WooCommerce if you want the demo shop content.
Both the theme content and theme options have been provided so that you can set up the theme to look exactly like the demo in a few minutes. You can find the main demo XML file, along with the demo content XML files for each of the example sites in the main download folder. This XML file is to use through the WordPress import tool, which can be found in Tools > Import > WordPress. Follow the steps to import the demo content and leave the final page to load with a confirmation that the content has been imported successfully (this may take some time).
Once you have imported the demo content XML, you will still need to set the home page by going to Settings > Reading, and under “Front page displays” select “A static page” and then select the one of the Home examples for the front page. Leave the Posts page blank.
You will also need to select the menu(s) in Appearance > Menus, for them to display on your site.
The theme options text file is to copy and paste the contents into the box provided within Flexform Options, under the Import/Export sub-menu.
If you want to import our revolution slider example. You will need to install the Revolution Slider plugin (Appearance > Install Plugins), and then open up the plugin from the left menu at the bottom. Create a slider, give it a title, and then give it an alias of “homeslider”. Select the full width display option, the change the grid width to “1170” and height to “450”. Click “create slider”. Next you want to click “Edit slider”, scroll down and select “Show Export/Import” and then import the “homeslider.txt” file that is included within the demo content folder.
NOTE: If you’d like to copy our revolution slider caption styling, we have included “captions.css” within the demo content folder. You will need to copy this this file to replace the file in /wp-content/plugins/revslider/rs-plugin/css.
If you have any issues with the import, i.e. any errors, then please contact your hosting to increase your php memory upload limit before contacting our support for help. You can see the recommended settings below:
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