Heh, I just applied Glanz Wax for the first time yesterday. I put it on the Regal after a wash and spot claying. I think you need to prep just like you would for any other product. Whatever your paint needs, that's what you need to do first. There's nothing different about Glanz.
It's an interesting product, and very easy to use. It smells like opening a bottle of turpentine, and has the same consistency. In fact, it even turns white chips and such the color of the paint, just like when you use tar removers and such. But then when it evaporates away, the white returns. However, it doesn't leave the paint dull looking like tar removers usually do. Instead it leaves behind a white haze that you buff off, and then the paint is very shiny and smooth. It's pretty neat stuff.
I think it definitely has some cleaning ability (not like oxidation removal or anything, but like bugs and tar and previous protectants) due to the incredible solvent content.
I thought your post was going to be a review? :nixweiss