it should be handeled as an occupied country, and in 1949, the allies get a "germany becomes independant again"-event after wich fdr is created properly.
Until then, there should be marshall-plan events that, hm, maybe just reduce the ressources and the supplies of the US, but patch up relations with GB and france (if they need any patching...). Include the possibility to extend the marshallplan on the eastern occupation zone and the sovjet union.