DRAW: RECTANGLE BETWEEN SELECTED LINES
RECL command draws a rectangle (or quadrilateral) between two selected lines or polyline segments. It allows you to close custom shaped holes easily.
POLYLINES: DRAW PART OF POLYLINE CONTAINED INSIDE OTHER ONE
APLUS can draw part of polyline which lays inside another polyline.
HATCHES: UNION HATCHES
APLUS can union selected hatches. APLUS will set style of first selected hatch to other selected hatches.
HATCHES: DRAW HATCH BOUNDARY
HBO command can draw boundary of selected hatch pattern. This may help you recover some lost information from a drawing.
PLUMBING: DRAW DUCTS
After setting some parameters you may easily design ducts both inside and outside buildings.
DIMENSIONS: DIMENSION LINES SHIFT
APLUS can detect dimension lines adjacent to one that was selected and then move them to a new position.
DRAW: DRAW DETAIL RECTANGLE
DETAIL2 command works similar to DETAIL command, but it uses rectangular window shape instead of circular in DETAIL.