To accomplish a couple things with advanced layouts, I had previously nested some Divs within other containers, and then set their positioning to absolute with Top/Bottom at 0px, and Left/Right values to achieve the look I was going for. (Basically a rectangular shape wider than a particular column)
After upgrading to RC1, those absolute positioned Divs inside other Divs no longer display on the front end anymore. I can’t quite figure out what’s going on with the CSS to cause this though.
If I inspect the page source, I can see the Div reflected in the code. Just something about its setup is no longer allowing them to be visible.