Guys I'm going to be using Atlas track to make my yard and am a little daunted by all the different codes. First will they all work together or are they different height? What's the difference between #5 and #7 turnouts? What would you use a 11.25 degree crossover for? I'm using code 55 I think and am wondering if this is going to be compatible with the articulated steam engines like the proto 2000 and the kato big boy?