Hey magggot!
At the moment the only way to overlap elements is by using offsets like here: http://laytheme.com/documentation.html#elements-with-offsets
But it's not unlimited layers. :/
You can put texts on top of any element in a row that is using "browser height for row height" as you can see here towards the end of the video: http://laytheme.com/documentation.html#use-browser-height-for-row-height
Maybe I will add this feature one day