I've completed all levels.
If you put power line on invalid square (like blue square or house) it will delete itself from existance.
Viewing post in Powerline Express jam comments
Thanks for this Pusio! I'd like to create more levels with an increase in difficulty to keep you a little busier! And yes, that's a known bug, I need to update the page to include it (I'll do that in a moment). I think I know how to fix it in Godot but I'm not going to have time to fix it before voting on the jam ends.