Click the folder icon inside of the file entrybox.  This opens the standard file selection dialog window; use this to browse to and select the desired results file.  The file entry accepts the full path and filename of the results file that contains the grid point force output for the current model.

Once you have selected an results file, loadstep names and IDs with grid point force output are saved to the database for use with all FBD utilities.  The loadstep name and ID information is retained within the HyperMesh database once saved.

If a new results file is required (or if the original results file changes) you must load the new results file into the database, overwriting the previously selected.