It was tough not to recommend this game, because I did enjoy it for a while.
At first I really appreciated how organic the game was: there were no clear directions, controls were written in the ground, no options, and you had to hold down esc to make your screen slowly fade into an exit. The game had nice spare looking style and sound.
The goal in the game is to return to the moon in a few different ways. The first few puzzles were extremely simple (for one of them you just wait in a post office and the mailman delivers you to the moon), but then a majority of them ended up being exercises in tedium.
Lunnye Devitsy is lacking. It has open world that is not interesting and stops being mysterious fairly early on. Sometimes messing up means having to trek back and forth between the boring areas. The controls and character are also a bit finicky and take more maneuvering than I think should be required. There are also puzzles that are all about guess work rather than puzzle solving (a completely blind maze, and then cannons take brute trial and error). And the "organic" aspects just got on my nerves: you can edit a text file to turn post processing on and off, you can enter full screen with "F" and you can't pause or change any other options.
This isn't a terrible game, it's just a game with terrible pacing and some poor choices. Its not even that this game is challenging on a puzzle or platforming level, because it's really not. It is quite simple, and, aside from the mentioned nuisances, the platforming is easy. The problem is that the game seems to deliberately want to inconvenience the player. Instead of being open, this game would have done better to be contained with levels and/or check points.
The price may be tempting, but I think you should consider other games.