I see where you are going I hope
This could be handy, but as it is, it just seems too limited. Some areas this could really shine would be to allow for the import of images for our background, and oh, maybe just have a way to set the background.
Basically if I am feeling like pimpin a div to a point that I want a visual editor, I guess I want a strong visual editor. But you seem to be onto something because I really do think it would be awesome to have an app that makes a single div with all of the bells and whistles without lugging out some behemoth app. Its just that this app doesnt really provide much of an edge over hand coding for me.
Oh, and totalling up the width of the box after everything is applied would be helpful too.
I am guessing that this app is going to improve. I dont think its all that handy to me in its present form. Ill keep my eye on it for now.
OsmosisNC about CSS Div Builder