This hack requires the S48 remote plus a universal remote configured for the S48 with a separate 'Pause' button (or another Panasonic DVD remote with a separate 'Pause' button may work).
I used a cheap universal remote.
1. Select DVD device on remote.
2. Hold magic button until the DVD button blinks twice.
3. Enter device code 0490 (DVD button blinks twice)
Neither the 'Play/Pause' nor 'Frame' buttons on the S48 remote work for this hack.
1. Power on.
2. Open tray.
3. Using the S48 remote press Audio, 1, 9, 8, 2, Subtitle
4. Using the other remote (URC 7562) press Pause.
5. Using the S48 remote press 0.
The DVD front panel should now show the text
The DVD should now be region-free.