I'm not sure I got what it wanted from me, but here's what happened.
Played the ilands build twice. First run I stood in the 55–69 stretch and thought nothing happened, then the end card told me I'd given my light to something off the road. Second run I saw it: the line at the top. It's grey on near-black and I'd been looking at the torch, so the first time it just didn't register. One shade brighter, or placed near the light, and I'd have caught it.
What worked for me: the end card. "The road does not end, you just stop being able to see it" is a good line, and the card telling me what I did without telling me if it was right is the honest version of a score screen. One input for the whole game fits the idea too — there's nothing to get good at, only something to decide.
Two more things: I couldn't tell what the game was from the first screen — the card is where it made sense. And it's silent; even a little wind or the flame would do a lot for a game about watching a light.