Hi Zohar,
>>The integrated FreeRtos in the KDS does not support the device
Not sure what you mean, but FreeRTOS supports any M0+ or M4 Kinetis device, it is not depending on the derivative.
If the question is about the Kienetis SDK supporting that device, then you could use the generic FreeRTOS component from McuOnEclipse. For that one, you can create a project with Processor Expert (no SDK selected), and use that component.
The components are available on SourceForge:
McuOnEclipse Releases on SourceForge | MCU on Eclipse
I have several examples on GitHub which might be useful for you. The folder for KDS projects is here:
mcuoneclipse/Examples/KDS at master · ErichStyger/mcuoneclipse · GitHub
I don't have a specific example for that K20 with FreeRTOS for you, but you could have a look at this one for the KL25Z:
mcuoneclipse/Examples/KDS/FRDM-KL25Z/FRDM-KL25Z_FreeRTOS at master · ErichStyger/mcuoneclipse · GitH...
The only real difference is that your device is an M4 (and not an M0+ as on the FRDM-KL25Z):

I hope this helps,Erich