What is the difference between the proposal creator and aggregator roles?
You must carry the Proposal Creator role in a unit before you can create a new proposal for that unit. The Aggregator Role, which carries all proposal level privileges, is granted by the system when a new proposal is created.The role is also granted to anyone who carries the default aggregator role for that unit (as defined in the user maintenance for the unit). In the proposal roles window you can remove the aggregator role from people if you want.