Draw recess and edit recess are almost the same as for every other element.

In this case, recess should be drawn before beams and blocks are drawn.

When you add a recess to the area the beams will be cut to length according to the recess.

When you draw the blocks you can get 2 different outcomes for the blocks.

If the block is in any way inside the recessed area the block will not be cut but if the block is entirely inside the recessed area the block will not been drawn.

This is due to the blocks are stock items and will be adjusted to size at the site.