Relic Castle

So i was trying to install EBS trough the mirror Marin posted and everything seemed to be going smoothly but then when i tryed to run and playtest the game i got this error message
Script'EliteBattle_Battle'line 22:NoMethodError occured.
unidentified method'isVersion17?' for nil:NilClass
i tried on both essentials version 17 and 17.2 can someone help