according to Ganesh Paisa in the SAP community Network:
AGR_* tables contains authorization data.
Some table are:
AGR_1250 : Authorization data for the activity group
AGR_USERS : Assignment of roles to users
AGR_SELECT : Assignment of roles to Tcode
AGR_PROF : Profile name for role
AGR_DEFINE :Role definition
But could be a hard piece of work to figure out already the essential connections... Let me know if you achieve it.