I played your game, and here's what I have to say.
YOUR GAME'S VOLUME IS SO ****ING LOUD, MY BROTHER CAN HEAR THE SOUND FROM MY HEADPHONES FROM MY ROOM TO THE LIVING ROOM!
• ITS SO ****ING LOUD! The game's volume is like those screamer sites those people troll others with!
So, just to be clear, you're saying it's too loud?? 
Well I agree! That's been one of the things on my task list but I'd been so used to just lowering the volume I didn't think it was a big deal. Obviously I was wrong. I've taken your criticism to heart and added volume controls for Master, Effects, and Music to the options menu. It may still need some refinement but at least it won't blow out peoples eardrums any more.
• The idea of this game isn't so bad, it's just a little hard to deal with.
• I went into the shop once, and then I couldn't figure out how to get back into it.
The shop is entered through man-holes, and they appear pretty regularly. Originally they were just black to look like man-hole covers to the sewer but I got tired of not being able to see them at all so I put a bit of white glow above them just so I could see them. The trick is getting to them - just walk over them or jump on them to fall in. Sounds like they may be still too hard to see, I had previously considered adding flags to them or having the shopkeeper pop out to flag down the robot, so maybe I'll try to modify them in some way to make sure they're more visible.
• The main menu music is really repetitive. And it resets when you go to the credits/options menu and back to the main one.
This is true, it's a very short loop from PartnersInRhyme. The loop and the reset behavior may be changed in the future, but right now that's still on my low priority to-do list.
• The main, and largest issue I have with this game is the fact that the default sound (for me at least) is over 100 DB.
Yeah, sorry about that. Fixed!
• I died pretty fast because of the amount of hazards in the first level... maybe tuning down the amount of spikes could help?
Well, I purposely made it difficult. And it gets harder really fast; more hazards, shoppe prices go up, batteries wear out faster, and so on. The key gameplay tactic for me personally is to collect cash asap and get to the shoppe to get a better battery, and then visit the shoppe regularly. As more content (BOSS, etc) is added I'll probably ease up on the difficulty to let players get further. I'd love to hear from anyone that can get to marker 30. Only takes a few minutes if you're good. I haven't made it to score 30 yet, though I'm really not real good at playing it.
• I recorded game footage, but Bandicam didn't get jack **** for whatever reason.
I'm not sure why it didn't record. I use the free Loilo Game Recorder and it's worked OK so far but uploading to YouTube skewed the audio by a second or two. The only thing that comes to mind is I did have the vsync setting enabled by default, but with the new build I disabled it and made it a setting in the Options menu.
• The game window took up my entire screen, but didn't go into fullscreen for whatever reason.
Yeah, v0.11 was set to do that. I've added a new full-screen setting to the Options menu based on your feedback, and now the game defaults to full-screen, so hopefully it will help others who try it out.
• I have a headache now.
Me too. I've put up with the high volume for quite a while. Thanks for letting me know what a major issue it is (was).
• I'm done here.
