How to trigger a matinee actor via a certain variable value

I’m quite new to UDK and I have started working on a shooting range. My vision is to trigger a matinee actor that opens up to allow advancement to the next level by shooting 10 of the targets.

I’ve based the range off of this video UE4 Tutorial | Use Array to Create a Shooting Range - YouTube

Any help would be greatly appreciated.

UE4 does not allow to capture variable changes, you either need to monitor it on tick event (but only if you need per frame reaction) or make a function which will set (or increase by 1) the variable and in same time will check state of variable, when it cross desirable value you trigger the matinee sequence

Also avoid call UE4 a “UDK”, UDK was free version of UE3 which support was discontinued for a while now, so if you say UDK people will think you talking about UE3 and make a confusion… but regardless this answer will fit for both ;p