You should be able to use the Package Manager to create a content package to export your users from under /home/users and apply to the other author environment. Note that the rights to the content is (should) be based on groups, and the reference is from group to user. So you might have to add your users manually to the groups or export the groups also. Then the ACL information of the content nodes needs to be exported from the primary author also.
/Ove