How do I install Child Theme for Responsive DirectoryPress site?

While trying to install the Lemisto Child Theme for my Responsive DirectoryPress Theme, I got the following error message >>
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Installing Theme from uploaded file: template_basic_Lemisto.zip
Unpacking the package…
Installing the theme…
The package could not be installed. The theme is missing the style.css stylesheet.
Theme install failed.
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Any idea what else I need to do to get it to install? Do I have to carry out extra steps with this Child Theme?