I have import several configurable product with mag mi and its working fine except for inventory management.
When i placed an order newly imported product quantity not decrease.However if i create a new configurable product and its associate product its working fine.
configuration setting in System-configuration->Catalog->inventory.
1)Decrease Stock When Order is Placed ->Yes.
2)Set Items' Status to be In Stock When Order is Cancelled->Yes.
Thanks in advanced.