Hi..
you need to attach the allocation structure you created to a settlement profile and then the settlement profile (ex for orders follow path spro->CO->Internal Orders->Actual Postings->Settlement->Maintain Settlement Prof) needs to be attached to a cost object (order, wbs element etc).
After that test it :by allocating cost to the cost object (order, wbs etc ) and try to run the settlement (KO88,CJ88 etc) and check if errors appear (that need some further corrections)
Cheers
Panagiotis