Just to make sure, do you get the "Charging this device via USB" persistent notification after connecting to the PC? You need to swipe down to see it, there's no special icon in the status bar except the flash overlay on the battery symbol. If you tap that notification, it should tell you "tap for more options", and these ought to include "File transfer"?
Regarding spare batteries, even after many of us have been searching the internet, the only known source is F(x)tec themselves, but none of the spare batteries which are offered on Indiegogo have actually been shipped so far (as far as I