Santa's Engineer is a spin-off from Simple Physics. It contains 5 new levels which is related to Christmas. It has improve the graphics and also have a slider for playback function.
This post contains the blueprints for Santa's Engineer. Many thanks to freaki1 who provided us with the blueprints.
iTune Link for Santa's Engineer
Spoiler Alert: Continue reading if you are stuck and looking for solutions to the game.
Feel free to share with us if you have cheaper solutions or blueprints.