Very good puzzles, maybe it's a bit overcomplicated to navigate in the UI to swap objects, but it's because of the Game Boy control limitations in my opinion. I would have made a simple press of a button that swaps to the next object in the list to fix that. Also for the rewind feature, I think I would have replaced it with a simple reset at each level, by making sure you also control the amount of resources the player has for each level and reset them properly.
The theme is 200% respected and prefectly used, I like the music that evolves when you turn on the machines, and for me it really is a Game Boy game in the spirit!