I took the cover off from under the radiator / engine front end and cleaned everything off. it looks like at least some of this leak is coming from the hose that goes from the PS Reservoir -> PS Pump. I had a single drop develop within a couple of minutes of starting the engine.
Additionally, I've got some weeping/"Sweating" happening at the crimp points on the crimped hose - where it goes into the radiator (the upper one, lower one OK). Lastly, I've got some more slight weeping/"sweating" happening on the hose at the crimp point on the "Expansion Hose" - i.e. the hoes that goes from the power steering pump to the steering rack.
I think I will replace a hose clamp and see how this pans out. I can see all the hose clamps on the reservoir etc have been replaced, but the one underneath the car.
Anyone had all 4 hoses replaced? What is the labour cost on this? Hoses themselves are not cheap... about $40 each for the 2 hoses leading out of the radiator and $65 for one hose leading out of the steering rack and $200 for the other. Looks like a total cost of 345 just in parts alone.
The hoses are parts 1-4 on here:
RealOEM.com - Online BMW Parts Catalog