Right, I have played around for hours and eventually got it to stop coming out of standby.
Control Panel\System\Hardware\Device Manager..
selected 'Mice and other Pointing devices'
then 'USB Touchscreen controller'
selected 'Power Management' tab, and deselected 'Allow this device to bring computer out of standby'
It works now, but I can't get S3 standby to work. But oh well, at least it is doing what I want!
