NXP Kinetis KM35 Metering Libraries

[SEIGE]

I am working on a metering application with the kinetis KM35 series, and I am having some trouble understanding the Low-power metering library. I have been using the application note AN13259 "Low-Power Real-Time Algorithm for Metering Applications."

While trying to integrate this library, I have found that there are actually many versions of this library in addition to multiple versions of the digital-filter and FFT-based versions. The examples in the SDK (imported through MCUExpresso) seem to have versions of these libraries that I cannot even find.

My questions is this:

1. What is the best way to determine what version of the library to use?
2. What is the best way to find the most up-to-date information about the LPRT metering library?
3. Am I working form the most recent and up-to-date application notes (AN13259)?