Thanks for playing!
Working with Godot's physics wasn't the easiest, this was probably a bit too ambitious for a 4 day jam as a solo dev. I put in a condition to break apart larger constructions if the velocity of each component is too high (it's a ridiculously high number, not something you'd get from just dragging it around), since the alternative is that all those parts become completely unusable. I've noticed that simple shapes and constructions work best and should be destroyed after their first use, but I agree it's not ideal since you should be able to build whatever you want. If I were to work on this outside of the jam I'd probably have to find some better way to work with Godot's physics or spend a good while writing custom physics.