Sorry to hear of the problem you are having.
It’s stuck to “Importing, please wait”.
In Chrome go to “Tools -> Developer Tools” and in Firefox you can go to “Tools -> Web Developer -> Console”
Also please make sure that your website server is allowing to access demo content on shufflehound.com and not restricting it by firewall or anything else.
At another point a tried the old method through Tools and it destroyed the database of my website!
Yes the old legacy method replaces all existing content as described in the below documentation.
In this case you can restore the old backup if you have taken any.