Hi JC,
As mentioned earlier that the issue is seen on three devices and only one among them is enumerating and we are able to flash the application on it successfully (But it is not working for the ZTC commands issued using Beekit tool). But when the same “SREC” file is loaded onto device using the Boot-loading mechanism it was observed to fail at programming.
Device 1: The one which is Enumerating
We tried loading the Demo applications (Application 1, Application 2) available with the installation of the Free-Scale Beekit (Test Tool 12).
Application1: KW24D512USB_Sniffer.srec
Sequence followed.
1. Interface the Dongle over JTAG to the host PC.
2. Run the JLink.exe over command prompt.
3. Issue command "Device MKW24D512XXX5"
4. Issue "Unlock Kinetis"
5. Issue "Connect"
6. Configuring Speed to the default values.
7. Loadbin KW24D512USB_Sniffer.srec 0
8. Downloading process is successful and the device is functioning well as the sniffer.
Note:
The downloading process is also observed to be successful when the same sequence is followed for the "802.15.4_SnifferOnUSB.bin" provided by you earlier.

Application 2: KW24D512USB_BlackBox_ZigBeePro.srec
The same above mentioned sequence of execution is followed for this Application, but it is observed to fail with same earlier reported issues.
Step (1-6): same as above
Step7 :
Trial1 <>Loadbin KW24D512USB_BlackBox_ZigBeePro.srec 0

Trial2 <>Loadbin KW24D512USB_BlackBox_ZigBeePro.srec 0xC000

It is observed to be the same error on both trials.
Device 2: The one which is not Enumerating but successful in erasing
Step (1-6): same as above
Step 7: Erase (It is observed to be successful)
Step 8: Loadbin KW24D512USB_Sniffer.srec 0 [Earlier reported error Observed]

Device 3: The one which is not Enumerating and also not successful in erasing
Step (1-6): same as above
Step 7: Erase (It is observed to be not successful).

Please check the logs attached