Same problem – did a clean install of a Theme could not install demo content – so suggest use your plugin but it sticks at restoring database.
Very frustrating – espec since demo content size only 8mb!
I updated Plesk to the latest version – disabled the offending plugging – rescanned all wordpress sites using plesk scan tool then re-enabled the plugin
Worked fine after that 😉
Hi Meg
No I haven’t touched the settings – I am not sure where to start looking as a first point to resolve