Same here. Got the same message & the game does not load.
Tried several browsers, updated them as well (thank you FF for all the legacy plugins ) and still have the same.

All I see is a div with id "hh_nutaku_all". The promo defer image is visible, so it seems to be a server issue. Whether it a server that's down, access rights, server quota, too strict security or just a misplaced file, we'll have to wait.