Triggering/hacking small ghost on a rope

I got a small "Scary Flying Ghost" from Big Lots this year ($16) - it's not very scary but that's OK as I was thinking it would be good choice when small kids come up.

It moves along a rope from adjustable stop to adjustable stop, swiveling and moving the other direction when it hits the stop. The arms move up and down as it moves, and optionally has a sound track (which at least masks the motor noise).

Alas, it sometimes can be triggered, and sometimes not. Even rapping on the case doesn't always work. I dangled some washers on thread taped to the body, and was going to trigger it by jiggling the support rope using a side rope to the window. Since it needs to hang from a rope to work and then moves around, there's no "try me" button input to trigger it. I'm thinking that maybe it needs to be hacked a bit.

It looks like it probably uses an H Bridge to reverse the motor, but the rotating to face the direction it's moving seems to be all mechanical. I suspect it monitors motor current to detect the mechanical stop on the cable and reverse directions.

I think I would need to either find a way to electrically trigger it (keeps the electronics including sound), or strip out all the electronics and control it all myself (H bridge for the motor, current sensor for detecting the stop, maybe add lights, use the speaker if I wish to add my own sound, maybe add RF transceiver for remote control). The latter is more work, but (1) may be the only thing that works and (2) would allow more control, like always stopping it at the same location. I might toss out the unscary ghost and substitute a skull or something in that case.

This would be my first prop modification. Any advice? Would I be putting too much work into a cheap prop?