In short override the Tick_Implementation method and use the parameter list defined for the Tick method. You are currently using another signature as in my current 4.7.2 headers.
You have to use the method with the _Implementation postfix because Tick is defined as BlueprintNativeEvent. That means it is handled by the UnrealHeaderTool and code is generated to link the calls correctly if you’re generating an dervided blueprint class.