Here is the link to the CEOP online form:-
'I am shocked that the official suspect in the 'presumed abduction' of a child has been invited as Guest Speaker by an organisation responsible for protecting children. May I remind you that recently, members of the investigating Police force stated in open court that the parents lied about the circumstances of the child's disappearance and that they believed the abduction to be faked.
In the use of the word 'presumed', you at least acknowledge that the child's disappearance may not have been the result of any abduction. What evidence do you have to rule out the McCanns as suspects?'
It will take less than a couple of minutes to send a complaint and, if nothing else, it will make you feel better to register your disgust with CEOP