Oh it's interesting to know you had the same turning issue with Linux, I'll see what I can dig up on that.
The secret endings are below ground level on the transparent floor and on the terrain at the lowest level.
No extra poems etc yet, they are just thank you's before the game self-destructs.
The win (for now) was getting to the top level with a little jumping skill and the poem itself.
I'm really happy with all the feedback on the voice narration, I just wanted to give people a way to look around and listen at the same time, rather than throw up a lot of text, cheers.