It is all working fine now.
topgog, you were definitely right with the CustomConfig dir path.
I did as the howto states... but it is wrong!!!!! The real path is /opt/MailScanner/lib/MailScanner/CustomFunctions/ this is what I do have in MailWatch.pm I have to admit I did not pay attention to this before and only today I have corrected this.
Thank you Rock and topdog for all you patience with me.