Why are some tines painted? Mainly to help you keep track of where you are on the instrument... but also to assist you in transferring notes from kalimba tablature to the kalimba.
There are now two different systems for painting the 17-Note kalimba in C. The Chinese system paints 5 tines, including the central tine. On the other hand, the Kalimba Magic system paints 6 tines.
If you want to use the Kalimba Magic instructional materials for the 17-Note kalimba in C, you need to use the Kalimba Magic painting system. If you want to use the Chinese instructional materials, you should use the Chinese painting system.
I have recommended people get their kalimbas unpainted, and they can color selected tines with Sharpie marker, which is removable, so you can change to whatever system you end up using, or even go back and forth.
And now - here is a way of painting the tines that embraces both the Chinese and Kalimba Magic systems.