Onions,
You are correct in this statement, and the airline will carry pax and baggae to the chosen destination but not necessarily on the same flight. This is by no means a common occurance but it does happen and not just with Ryanair.
Sir,
All unaccompanied or "Rush" bags must have extra security checks made - the detail of which are not appropriate for a public forum, suffice to say that extra security checks are undertaken.