Excellent critique/bug report, I have to say! Thanks a lot!
Let's answer, then:
1. That's intentional;
2. You're not the only one having issues with this achievement: I'm thinking of a solution and I'll let You know! Thanks for the feedback;
3. The first half of the game needs to be almost the same of the original, it's for "lore" purpose;
4. Game Maker is really tedious with 3D sound (and I'm not a great programmer): really sorry about that, but the sound won't change based on the direction (it will, however, change when moving). If I come up with a solution, I'll revisite that portion;
5. Didn't knew you could go there, gotta fix it;
Thanks for the feedback, benzoingum, I'm really happy you enjoyed my game! But... How do you know about Loneliness?