but i think i don´t get it right ..

I have my modell done ... and as I said I just working on the JCM .. I´ve just bought morph clothes from Dimension 3D .. Now when  Michael bends his arm the JCM -Morph should just work say only lcollar + l shoulder + lForeArm but I ´m not sure Im doing something wrong .. 

Is there any Tutorial out there how I can setup JCM inside newClothes ??