The game started with "You win", on day 8, and a button for endless mode, which felt odd. I restarted just to be sure.
Your instructions say press ESC for the crafting menu, but I found that it opened with Tab. Since things were not working I started pressing random buttons and found that the number keys do various things, including giving lots of resources, which is the only reason I played more to see what the game offered.
It was not clear how to play at the start. It seems like you have to be on top of something to pick it up, in which case you are almost just clicking on yourself after moving on top of them. I had moved near items to pick them up initially, and was not sure how close you needed to be, but it was much closer than expected for a use the mouse to pickup mechanic, and it felt inconsistent, like sometimes the player or enemies got it the way. Similarly, throwing items to use them was not initially clear, and took several tries to figure out things worked. The 2 layers could use some explaining. I found that the "generators" are on the main layer with the turrets, though do not spin themselves or look active. All the gears go on the second layer, and do spin when connected to a generator. The turrets don't have any indication of when they are active or not. I do think that having the gears faded out is good to not clutter the screen. The second layer just needs some carity as to why it exists. I would highly recommend taking some screenshots showing how things work, along with a better description on the game page.
The first wave comes too fast before you really have time to learn or build, though it seems that you do not lose anyway. There looks to be an interesting game here, but it really needs some explanations and probably starting at an easier level with a chance to learn and build up.