Hi Ali ,
It does matter what profile type you use. per the note I gave you the combination needs to be active. As for global dependency or local. Local dependencies are assigned to the object so If the OD is only valid for that object then you can use local otherwise you will need to use global. Variant configuration all depends on the requirement you have.
As for constraint, they are not very easy to use. Please check the documentation in help.sap.com for the details. That can explain the best
Thanks
Amber