There are 2 bugs i found
1) When a redstone repeater is already powered, it cant be stopped using a redstone Repeater as a lock. Only when the lock is activated first, will the lock work.
2) When both the main redstone is powered as well as the lock is powered, deactivating the main redstone will still power redstone past the redstone repeater lock. When the lock is disabled, then the main powered restone will die to.