Probably an 'ancient' request: but how about those composite slabs, acting like composite walls. Set your priorities straight and 'all' connections are made properly and immediately...
[EDIT] In other words: connecting floors to walls is as simple as connecting walls. No more needs for deviding your floor into 3-4 different 'layers' (structure-screed filling-finish)
Following up: those section-connection should stay connected when moving anything in either direction...