The original navcore (8.010 is the latest if I recall correctly) should work with TMC.
If you have an older one, connect to TTHome, run update my tomtom and select the "tomtom application".
Now you will have an unpatched tomtom which will not be able to use downloaded maps, so you will have to patch it again if you use said maps.
If you are willing to experiment with an SE navcore, (ALWAYS BACK UP your original configuration on your PC!!!) you can try 8.417 or 8.562. Read the readmenot.txt file for optimal settings. I would choose the following switches in setconfig.txt: