Versions
CraftBook version: Craftbook-3.10.3 and CB 5.0.0 snapshot
Bukkit version: PurPur 1022

Describe the bug
When using Elevators from CB5 - If a [lift updown] does not find a elevator node above it - it will crash the server!

To Reproduce

1. Make a Lift UpDown sign
2. Attempt to go up

Expected behavior
If looping is enabled - attempt to place player at the next elevator in sequence, else message the player that there is no available elevator

Screenshots
N/A

Additional context
Added log of the stack trace that occurs when the sign is interacted with.
2021-03-27-5.log

Fixed.