Thank you Joop for a quick reply. I will re-read the manual.

I have a question - If I download to a usb hardrive and activate everything from there will the usb hard drive need to be connected at all times with fsx ?

Impressive scenery, thank you, but Im am having problems. I have succesfully downloaded these - EHVK, DR and the libraries ( but the checkbox tick is greyed out). I am having trouble with the rest of the downloads and keep getting this message ... system. NullReferenceExeption: Object reference not ...