Daniel - I think you’re looking for a more technical answer than I can supply. I’m still learning about the emon/OEM code.
I have an emonPi and I use the standard Nov 2016 image. So the Inputs and Feeds and pulse count software are all part of this build. I did not add anything extra to the emonpi_interrupt_pulse.ino code.
I am guessing you are not using the standard image. Is this correct?