Burnham Revolution piping?

John T_4

On my recently installed RV4 there are some differences between the piping diagram and the actual piping, and before I call the installers, I'd like to know if these are an issue or not. 1)No air vent on return. 2) No ball valve on supply, between isolation valve and air vent. 3)Cold water supply is piped... shut off valve--reducing valve--check valve then enters above expansion tank, diagram shows check valve--shut off valve--reducing valve then enters above expansion tank. 4)Taco 007-F5 circulator is mounted horizontally with cartridge and junction box on top with junction box upside down, I thought I read that the junction box cannot be in the six o'clock position. I'd just like to be a little knowledgable, before I call, or if its piped OK as is I can relax! Thanks for any input!!!