There seems to be some softlock bugs with ending a level that slipped past me. I actually reuploaded it a couple times before submitting cause of ones i noticed in final testing, but seems i still missed some unfortunately. Didnt realise there was any bug with the delete, thanks for that heads up - if i do any more development on it ill definitely need to keep an eye on that.
A more in depth tutorial is definitely something I wanted, just didnt have the time for - I hoped that the basic descriptions would be enough. I wanted some mechanics like the heat transfer to be fairly abstracted, but i agree that some sort of clearer indicator would be a big improvement.
The music was admittedly thrown in as i felt it was awkwardly silent without any, but thats why the mute button was there lol.
Glad you enjoyed it (when it was muted, and you figured out the mechanics, and it wasnt breaking on you)