If you are/were a member of the Team AnandTech RC5 effort, then you already are a member in OGR.
If you just need to force your client to do OGR instead of RC5, then danzigrules is close.
Since OGR is the "default" contest, in the line of "preferred order" just make sure that there is no "=0" after the OGR entry
It should just be: DES,CSC,RC5,OGR
The order is not important anymore. Even with RC5 first, it will do OGR if possible.