I don't know if it's okay to post Mawekl's answer here.
Quote from Mawekl
Hey, my friend from Dragon Sector was hosting the site, and I've completely lost contact with him (at the time the server went down), still waiting for a response. He even deleted his twitter account.
I have files like site and challenges backuped, but unfortunately the last database backup (users/scores) is from like 2 years ago (my bad).
I hope my friend will be back and answer.
In the worst case I'm thinking of creating Security Traps v2 with old challenges and new ones.
I'm sorry for the unavailability of the site
The site was/is from another world... a gem in security.
If the scores are lost, not too bad.
The challs were the gems