Sorry, I don't have a demo setup on my system of Sage CRM, so that limits the information I can place in the setup screens. However, in Sage 100, you create a link to each Sage CRM dataset (top window in screenshot, Sage global settings), then in each Sage 100 Company you configure for that respective Instance. In Sage 100 you set user security to the integration, and in Sage CRM you can set security for each dataset, i.e. if a user has access to ABC in Sage 100, but not XYZ, they will be able to (based on CRM security) work in the CRM records tied to ABC, but not XYZ. On the CRM side security will need to be set accordingly.