Use a script in File 1 to open File 2 and perform a script in File 2 that does a show all records on a layout for each table from which you will import this data.
Thanks for your answer, but that's not possible, because file 2 can't be changed anymore (data file of a runtime solution).
Why does that keep it from being changeable? Is this a runtime file that you created or from another source?
If you created the runtime file, you can open it with FileMaker Pro and add a new script as long as you are still able to open it with full access permissions.
If you can't change the file, you'll have to log in with each table.