mechanical nightmare maybe, what if the crossing light rocked left-right a couple seconds when target hit..
seen quite a few low voltage micro gear motors 150-180 rpm range.

RRXing lights don't stay on so I think it would not look so good.

Looks good, but a little too complicated. I like it because it's not a pencil sharpener.

I drilled a hole in the headlight of the metal train and then another hole down from the smoke stack. I put a red bead on top of the stack and a white bead on the headlight, both to reflect the light. I added a single white led inside the train. I have not installed it yet, just checked it with batteries. I like the crossing sign idea. How are you connecting the sign? I would be interested how/where you end up hooking these up. Once I get mine installed I'll report back.

I have been thinking awhile to put model steam locomotive with tracks (n scale) above that lane or somewhere. If you hit the target, then it would advance until track ends. At the end I then would somehow make locomotive to reverse (probably with some switch).