I feel bad for the people that made this game so I'm just going to😀...

Okay, you see the part with all the snow and the spinning red lights and so on?
Okay, cut all that out! It's making the game lag and run terribly!

I don't know why people feel the need to put what is essentially spam in their games.

Trust me no one's going to miss it and it doesn't add anything useful or fun to the game.

bug in tutorial, i can leave the map. and start of second level very bad.

I gave this game another try, but I still say that both controls and the level design are absolutely horrible.
As for the 1st: I adviced you to lower the gravity a bit and fix the hit detection, but neither has been done;
As for the 2nd: lots of levels, especially the secret ones, are designed in a way that make barely possible to even begin a level-you are crashing before you actually can do anything and since the controls are not very responsive... I even cannot begin the second part of level 9 because just after I enter it the ship just dives down to the wall completely not listening to me pressing the up arrow.
The game isn't very enjoyable, you constantly got a feeling that you are fighting controls and bad physics. In some levels you may even get hit, but not die and continue flying without any control of the ship until you will "die" again. It is also possible that you will get stucked inside a wall, between the obstacles etc. and since on the regular level you cannot return to the level select by pressing escape you have to reload the whole game. While playing you may also get confused not being sure if you entered the next level, a secret level... You mentioned that some secrets have been added on levels "0_0", "1! 1--0acb1" and "1dangerous1", but the levels do not have any names. You don't get a notification like "entering level <insert name here>".
One suggestion: when I already found a secret level why it cannot be marked in the level select menu?
I remember sending you a link to a similar game, but much better executed, you should try to find some inspirations there to rework and improve your game, because a lot of potential is being wasted here.

Not bad at all but it's difficult. Impossible to manage without crashing, we have to remember the paths by failing again and again. I think some more space to see what's coming (zoom out) and more time at the beginning of levels (maybe a keystroke to start moving?) would help a lot .