For what you describe, I think you need to take a step back and rethink this. You don't need two machine and two database systems to control access to the data.
Use Manage security to control access to different parts of your system. Teachers and Researchers can be granted a level of access and passwords that enable them to access data that your students cannot. The account used during log in can even control which layout is selected for the person logging in.
Actually, both proposed database files will be on a single machine, and the problem isn't so much security as ensuring that students don't end up on the Teacher/Researcher log-in page; that would cause problems for the teacher in the classroom. Since all three parties are accessing the database through a single log-in page that I've created (not the built-in log-in system), it is possible for any of the three to end up in the wrong place (see attachment). The idea behind splitting the test off from the research stuff is to simplify log-in for everyone and prevent confusion and delays in logging in.
I think that you are suggesting handling security at a global level, before the students/teachers/researchers access their respective areas. However, students will not have accounts before they take a test. We won't know who they are until their teacher gives them the test. As we expect potentially dozens of teachers giving the test to hundreds or thousands of students, pre-registering the students would be a daunting task for the database administrators, much less for the teachers. Therefore, the log-in process incorporates procedures for looking up students in the database; if they have a student record in the database, a new test record is associated with that student record, but if they don't have a student record, one is created for them and then a new test record is associated with it.
Teachers and researchers have a separate log-in page. New teachers and researchers must request an account; a form is provided in the database for emailing an administrator. They'll receive either approval and a password, or denial.
I suppose that the students could use a single password to log-in via FM's built-in log-in/security system, and then enter their student ID number to access the test itself. But new teachers and researchers would have no way of requesting an account.
Believe me, if you know of a better way to handle log-ins, I'd be happy to use it. This is all new to me, and I welcome any and all suggestions!
Students can be given a default, low level password to use to log in and the privilege set assigned to an account can be used to identify whether or not the current user is a researcher, student or a teacher and then take them to the layout that is appropriate for that category of user.
And FileMaker scripts can be set up to manage accounts so you can issue a "new user" password that automatically takes the user through the process of entering a new account name and password--which then becomes the account name and password that they use from that point forward. So even if you need individual accounts for each student, you don't have to manually create them.
Ah, I didn’t know that I could send users to different layouts depending on their logins. or that “new” users could be automatically assigned an appropriate password. I’ll start working on that right away. Thanks!