Elevator help

I ahve created an RPQ, and I have created a demon-hunter base with holding cells. Basically, I created a number of square wholes in the ground and placed elevators there with scaling values of 0.9. I haven't finished making the map but I have created the following trigger for testing purposes:
RaiseElevator
Events
Player - (Local player) types a chat message containing +elevators as An exact match
Conditions
(Destructible-type of (Picked destructible)) Equal to Elevator (2)
Actions
Destructible - Pick every destructible in (Playable map area) and do (Destructible - Set height of (Picked destructible) to ((Height of (Picked destructible)) + 1))

And this trigger:
LowerElevator
Events
Player - (Local player) types a chat message containing -elevators as An exact match
Conditions
(Destructible-type of (Picked destructible)) Equal to Elevator (2)
Actions
Destructible - Pick every destructible in (Playable map area) and do (Destructible - Set height of (Picked destructible) to ((Height of (Picked destructible)) - 1))

When I type the chat messages in-game I see the elevators rise to ground level but the units on them cannot leave them and units outside cannot pass over them. Please can someone help as this is quite important to my map.

Below is a picture of my problem:

Try using the open walls for elevator action.

If I do that, what do I need to set (eg what 'wall' should I open)

Try opening all walls.