There's in-game notes about 3 levels F6 "THE CURRENT DIMENSION, F-6 INHABITED ISLAND", D6 "ANOTHER DIMENSION D-6 IMITATION ISLAND" and D2 "ANOTHER DIMESION D-2 IMITATION ISLAND". But actually I see just D6 (start level) and D2 (by railways level). But what's about F6? I'm really interested about the game lore and one more possible level)
Actually the game is quite precious, it's not complete and quite little, but it's having nice potentional.