I bought Oknytt, Gray Matter, and Lost Chronicles of Zerzura from ShinyLoot during their sale. I already had disc versions of the last two, but it's nice to have DRM-free versions and they were a bargain at $5 each.
Sale's over now though.
Oknytt is definitely a night-time game -- to be played with no light in the room at all other than the computer monitor.
"No light" as in "if you have a light on your monitor, put an index card over it or hide it behind a sweater or something." But once your eyes get accustomed to the darkness, it gives the game a certain otherworldly feel. If you've ever gone outside at night and noticed how even familiar places seem different in the dim lighting -- especially in woodsy areas -- it's sort of like that.
The ShinyLoot purchase of Oknytt included a downloadable walkthrough separate from the game installer file. Not quite MaGtRo-quality, but it's there to help out if you're stuck in the darkness. One thing I wish they'd have included is a file with descriptions of the different creatures you meet in the game.