The testimonials plugin that you are using is not designed to be responsive. It is also not a Shape 5 plugin; you'll need to file a support request with the plugin developer.
As for the mobile footer showing to high on the site, I believe that is solved in a newer version of the framework, so you'll just need to update to the latest version of the
Vertex Upgrade Patch.
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To install the patch:
1. Download the
Vertex Upgrade Patch.
2. Back up your site (just in case).
3. Copy the vertex/footer.php from the theme folder to somewhere safe (you'll be putting it back after patching).
4. Delete the vertex folder from the theme (nothing else, that is the
only thing to delete).
5. Extract the zip file containing the patch, and upload it to the theme folder through FTP, choosing "overwrite" if/when prompted.
6. Copy the footer.php file (from step 3) back into the vertex folder of the theme.
That's it.
Or, to put it a different way:
1. Back up vertex/footer.php.
2. Delete the vertex folder, then upload the extracted patch to the theme folder.
3. Put the footer.php file back into the vertex folder of the theme.
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