Shortcuts

CTRL+S - Save the current part
CTRL+Z - Undo
CTRL+SHIFT+Z - redo
CTRL+D - Duplicate the selected shape(s)
CTRL+G- toggle grid snap
CTRL+P- toggle preview
Delete - deleted the selected item or items
SHIFT+up - move the shape up by the amount of the grid spacing
SHIFT+Down - move the shape down by the amount of the grid spacing
SHIFT+Left- move the shape left by the amount of the grid spacing
SHIFT+Right - move the shape right by the amount of the grid spacing

Move Tool

SHIFT + Click- Add part to selection
CTRL - Click - Remove shape from selection
SHIFT + Drag - Contrain Movement angle

Line Tool

SHIFT + Click and hold shift - Draw a new smoot point
SHIFT + Move to next point - Contrain Angle of line

Shapes

SHIFT after first point to contains to center or make equal width and height

Copy

Space Bar Copy the selected object to the current position