Hello...Im fairly new to the SDS 200 and wanted to down load the NXDN software from unidens site. It asked me for my ESN number witch i am taking is the one when i go to my firmware version witch is a 14 number SN but i can only fit 12 numbers on the first line at the down load site. Now the SN on the back of the unit its self is only 12 numbers and 12 will fit .What SN number should i use? The second line below the first is for a checksum number witch i assume is the last 3 digits of the firmware version of the SN...Thanks for any help I hope this is not to confusing .