Hi,
you can put it in PortableFolder/ next to the executable. Appdata/Roaming/vifm/ should also work. If you have $HOME defined, you can use $HOME/.vifm. To check which location Vifm picked and whether it matches your expectations use
:echo $VIFM
:echo $MYVIFMRC
The second issue should be resolved by this as well.
Documentation specifies priority of locations which are checked on startup.