Why not use my 
Sensor Light blueprint. Use your reed sensor on the trap door as the trigger (if you cant select it copy paste the entity ID into the input), add your lights and set the delay to your liking.
Blacky 
Why not use my Sensor Light blueprint. Use your reed sensor on the trap door as the trigger (if you cant select it copy paste the entity ID into the input), add your lights and set the delay to your liking.
Blacky