I think getting to the system setup screen is truly only available to Administrators and I'm not sure you can change that. Some other things to check (if you're not trying to grant permission to that specific screen) would be if the user has all permissions beginning with FAM & BG. The BG ones are less obviously part of FAM, but they have to do with the way the system processes transactions. Stands for Background I think. There is a Fixed Asset Management role that comes installed with the bundle that I believe has all the FAM permissions. You can check that out too.