Additional BardecodeFiler Services
You can actually configure as many BardecodeFiler services as you wish, though you can only edit settings for the first 4 services through the BardecodeFiler.exe app.
Section 7.3 of the manual explains how to configure extra services, however you will need to configure the set up files in C:\ProgramData\Softek Software\BardecodeFiler manually for each additional service.
For example, to install BardecodeFiler Service(4) head to C:\Program Files\Softek Software\BardecodeFiler and run:
BardecodeFilerService.exe -install 4
And then under ProgramData copy one of the existing config files to service_settings(4).ini and then edit the folders in the ini file using textedit or similar.