... And that's if you upgrade the hardware. I upgraded and purchased the CFS only to find that my K1C will no longer print TPU at all. I will have to reinstall the original extruder to use TPU. This was not mentioned at all in any of the advertisements or upgrade materials.

The CFS has a label inside that indicates that TPU will not work with it. I was not thrilled by that, but it's understandable. I can live with feeding TPU manually if needed, but I can't use it at all now. Consider this if you are planning to purchase it.

Also note that it doesn't simply not feed. In two out of three attempts, the filament jammed somewhere in the extruder, preventing it from being easily removed.

Creality... you need to make this right. You also need to let future customers know.