Very atmospheric!
I think i would prefer the paths to change only when they are in the dark, because this would add a touch of mystery to the whole thing— “Didn’t i just pass here just a moment ago?”— that gets somewhat broken when i can see the paths moving all of the sudden.
I kind of noticed that it is too easy to get stuck, either because i sent away the last firefly or because the paths change and cut me off. I guess i find it a bit “unfair”, but have no suggestion on how to improve it.