If I place a barrier w/Contruct on the grounded area just below elevated terrain, are figs who are on the edge of the elevated and therefore just above the barrier (posssibly "touching it") in need of a breakaway if they wanna move?

from what i know...barriers are blocking terrain. if you stand on a building you can see everyone in range. however blocking terrain will block your line of sight. so it is taller then the building meaning you must be adj. to a barrier if you are at the edge of a building. if i am wrong i have a ?. in the same situation. if some one takes knock back and lands on a barrier created next to a building do they land on the barrier. does the B get destroyed. and when the B is removed do they take fall damage

The elevated figures are not adjacent to the grounded barrier, so they would not need to break away.

The figure would stay on the elevated terrain and be dealt one clinging damage.