Background Image & General CSS Help on Form Popup

I am trying to recreate this form inside Popup Pro...

http://redtea.com/test/pop-ebook-16-ways.html

However, no matter what I try, I can't get it to work. CSS code get's ripped out of the popup from the plugin. I know it's just one little trick I am missing to get it to work in Popup Pro.

I've already granted you support access.

Thanks in advance!!!