I too am visiting RIX (in Sep). I am going on BA - in your case you can go either ORD-LHR(AA), LHR-RIX(BA), RIX-LHR-DUB(BA) etc...or ORD-LHR-RIX-LHR-DUB (BA) - but I am not sure whether AAdv lets you use BA transatlantic sectors for awards??
[This message has been edited by alect (edited 05-12-2003).]