Hi,
I have windows vista. When i first installed icloud it worked fine. my husband then got an iphone so i made a new user account on the pc so he could have his own photostream. I found after doing this I had the same problem as you on my original account (can't check photodstream on control panel). So i made a new user account for myself. Our PC now has general (my old user account), Rob and Alex. The general account has the same problem as you, Alex and Rob work......to a degree.
For you Socacofi making a new user account and activating icloud on it may work. If it does, and the pics download to a new account, move the pictures to a folder on the public file then you will be able to view them on your usual account.
I say it works to a degree as I have the following problem with both my and my husbands accounts: The photos won't stream unless i uncheck photostream on the icloud control panel, sign out then sign back in again, reselect and apply. Whrn I just had one icloud they would stream automatically as soon as I had taken a photo. E,g I could walk in the house after taking photos while out and the pics would be in the photostream after 5 mins. I have ensured all the permissions are set to full control for all accounts and have tried resetting the photostream, reinstalling and changing the folder the photos are set to stream too.
I was told by apple when intially enquiring about having two photostreams that both icloud accounts could be signed in/running at the same time but even if I have one account signed out the other still won't stream properly. It's not the end of the world but its annoying as it previously worked fine.
I called apple but the guy I spoke to 'Adam' but he didn't really understand what I was saying and said that this is how icloud was supposed to work. He said it would only stream if your phone was in lock mode. I tried to say it won't even stream in lock mode until I sign in and out again (basically refresh it). If I take another photo after getting a batch of pics to stream by this method, I have to sign in and out AGAIN to get the second lot to go over.
Any clues?