Hi andre...
The BB1 appears to take a 'shadow copy' of the 'b2settings' file during the boot up sequence and holds it in memory. What is happening here is the after you have made the changes to the 'b2settings' file and you then power the BB1 down, the 'shadow copy' is written back to the /media/sd3/b2settings file. Thus your changes are lost.
The method that I use is to open the BB1 up, and remove the microSD card. I plug this into a PC, then locate the 'b2settings' file on the microSD card and make the necessary changes to the 'b2settings' file with Notepad++ (don't use Wordpad or Notepad as these can add spurious end of line characters which will cause problems).
Then plug the microSD card back into the BB1 and power it up. This reads your updated 'b2settings' file into memory and you will find that your changes are preserved.
Regards,
Peter.