The elevator on the ground floor

A wooden elevator stands on the ground floor, but pressing B on it does nothing.
Nudge 1Where to look
The village's elevators are locked. Each one has its own key.
Nudge 2A stronger push
The key for this one is lying on the ground floor, past the spikes.
What you needOther problems to solve first
Solve these first (each opens its own page, no answers on the way):
Show the solutionThe whole answer, with a video
Pick up the key for the ground elevator, stand in the middle of the elevator's car and drop the key (B). It unlocks the elevator, which takes Dizzy straight up. From then on, stand in the middle and press B to ride it.
Why it works
Each elevator stays inactive until its key is dropped on its car. The key also sets it moving the first time.