The address I used:
Sue Johnston
KEN MCREDDIE ASSOCIATES LTD
101 Finsbury Pavement
London
EC2A 1RS
UK
I received today (16th July 2013) A signed photo of her own, my photo back unsigned and a letter saying how she cannot sign personal items.
Picture:

At the top left there is the letter
At the bottom left there is my photo back unsigned
On the top right there is her own photo signed
Underneath is the envelope