I have found macros to convert a single assembly to a part, but it does not address the configurations, on the open configuration. (Reference -
https://forum.solidworks.com/message/291831#291831 Save Assy As Part (Exterior Surfaces).zip (10.5 K)
I have also found a nice macro to convert configurations to multiple formats, EXCEPT SLDPRT. (Reference - https://forum.solidworks.com/message/74659#74659 DocExport)
The functionality of DocExport with the addition of saving configurations as parts would be perfect.
SolidworksApi macros