justifun
First you need to make the box movable.
velocity way:
set velocity to rect((mouse.x-sprite.x)*10, (box.y-box.y)*10)
and set it to 0 when not dragging
acceleration way:
Keep the box from falling from gravity with:
on box prestep
--- apply force rect(0, -gravity*mass)
and give the box a max speed at the start of the layout.
then to move:
apply force rect((mouse.x-sprite.x)*1000, (box.y-box.y)*1000)
and when not dragging give a slowing force.
apply force rect( -velocityx*1000, velocityy*1000)