This site should be clean & safe. I think (guessing - Fencer would know for sure) - I think that the pictures on this site is actually hosted on a different "server" then where the pages are loaded from - and I think if a browser is set at the highest security, it will view a site that gets pictures from a second site as a security risk. (That way some scam artist does not pretend it is PayPal.) Again, I'm guessing here.

What exactly are the messages / security warning you are getting?