Cumulus Support

Which is the preferred site to upload to?
I have registered with Weather Underground, on Cumulus settings, for ID do i put (a) my log in e-mail address, (b) authentication code (c) PWS ID code, i.e. "ishropsh8"

I upload to both. I suspect Wunderground is the most popular.

You need to enter your station ID, otherwise Wunderground won't know which of your (possibly many) stations you want to update.