My 525i wont start turns over but will not start has fuel pressure at fuel rail.

it seems you need use BMW ICOM to check it.

seek daig and est from your mech

It will be hard to test this further without diagnostic equipment. You need three basic things to start your engine: good engine compression, fuel, and good ignition spark. If you're suspicious of fuel I would recommend basic fuel pressure tests next. One test you could do, if you're careful not to cause a fire, would be to remove the fuel rail with the injectors, wiring, and fuel lines attached. Then have someone crank the engine and see if you're getting good fuel spray out of the injectors. Of course be very careful because this is a potential FIRE HAZARD.