freeware versions 
The limitations of freeware version:
x2ipi72 - 2000 readings, 81 electrodes, no IP data;
x2ipi48 - 500 reading, 48 electrodes, IP data support 
full version (Sign)5.06.17. The last version was not correct.
For Guardant Sign dongle ( MS Windows XP to Windows 10 ), all drivers are included
full version (StealthII) / 03-01-2017
For Guardant StealthII dongle (public code FS0K10T)
     Hardware key (dongle) software drivers and  diagnostics
guardant.comGuardant drivers page 
GrdDiag.exeDongle diagnostics
   Sequences examples (Wenner-Schlumber, Dipole-Dipole, Pole-dipole arrays)  
 Syscal-Pro Switch 72TXT format, see details
 Syscal-Pro Switch 48TXT format, see details
 Terrametet LS (4x21)XML format, see details

Supported by IRIS Instruments