Juggling a single beam between boats is a lovely idea, and the moonlit islands under the aurora look great. It took me a moment to get that boats only move while lit, and then I switched off boat 2 right before it reached the harbour, oops. A small arrow on each mirror showing where it will point next would make switching feel less like a guess.

For some reason, on level 2, I kept getting some ships appearing right under the number 1, and being unguidable.

interesting idea! Liked the music and sound and graphics.

Could have used a more interactive tutorial perhaps. 

A bit wordy in places that it wasn't necessary to be wordy in