problem importing demo

Hi! I was importing demo content manually as you descrie at http://documentation.hb-themes.com/highend/#demo-import. And I got an error message, then I tried to delete all menus and tried again, and got the same error message, so I’ve been trying for 5 times and all the time the same error message. Below you will find my “printscreen” attached.
Thank you very much in advance for your help.