This is what I did:
Set Application Properties->Eye Distance(3d) to 500.
Enabled "3d Layering" for the 3d layer.
For both the 3dbox objects I set the "Rise scale" to 1.
Set depth of Wall3d to 64.
Erased front face of Sprite3d.
On event 2, the actions for setting 'distance', X and Z were adjusted.