PEG007 - If it is any consolation I have made several attempts to download/install SP1 using every method possible. I downloaded and run the System Update Readiness Tool (for 64bit) - disabled Firewall/Anti Virus but it made no difference - SP1 gets to 99% and fails. Same error code as you get.
My opinion is that it is because most of the updates contained withing SP1 are already downloaded and installed so I have no plans to make any further attempts.
PC is flying at the moment so I am no longer concerned with SP1 - the only thing is that it doesn't show up in Computer/Properties.