I had some trouble getting doctype to stick in your example (i.e. I entered it in page properties and then went back to page properties and it was blank. Only worked in your example by pasting doctype to the top of the html) but I could intermitently replicate the problem.

 

Please compare what you're seeing in the editor with the stand-alone page: http://www.shoptalk.co.nz/BeautySecrets.html

 

Below is a screen dump of the problem in the editor example on your site with doctype in place:

 

 

Thanks

Thomas