The upgrade procedure is described in the User Manual.
IMPORTANT:
Verify which Revision of KT-107RB you are upgrading to ensure that you use the correct FW file. Using the wrong FW can cause the device to be unusable: KT-107RB Revision 01 contains R: 01 on the label on the rear of the unit and R: 0104 or higher on the label on the box.
KT-107RB Revision 00 does not contain an R # on the label on the rear of the unit and contains R: 0003 or lower on the label on the box.
See details in the Release Notes