Here is the answer to "What fare codes Star-Alliance round the world tickets use" (taken from the official Star Alliance RTW Ex Switzerland Quci-REference-leaflet):

First Business Economy
UA A D B
TG P J M
SK F/D C B
RG F C H
LH F D B
AC F C B

All these fares qualify for mileage-account and status miles - also for use of upgrade-vouchers/mileage-awards for upgrades from eco to business for individuel segements - but (since two months) no upgrades from business to first anymore. And the always book the flight-number of the actual carrier (no code-share-flights) on these tickets.