UIDMap

Within a world's save folder, in the circuitsMod directory, there is a file called "uidmap.nbt", containing mappings from the folder names of Circuit Block types to their internal unique identifiers. You probably don't want to mess with it, unless you encounter one of the following situations:
 * You're trying to load a save file from someone who dropped in a circuit whose name conflicts with one of the circuits you dropped into the mod, but the functionality of the two circuits differ. In this case, you should rename the circuit folder in their save directory (e.g. "Multiplier" -> "MultiplierFromBob") and then change the uidmap to point the new folder name to the old UID (e.g: "Multiplier -> 1" -> "MultiplierFromBob -> 1")
 * You manually renamed one of your circuits by changing its folder name. Update the name in the uidmap to the new name.