connect computer to hermod usb device port.
add a midi out effect to tracks you want to record.
in midi out fx set port to “USB device” (this means the hermod acts as usb device to the computer)
in midi out fx set midi channel, you probably want a different one for each track
in ableton ensure the hermod is enabled for input
preferences -> link/midi -> hermod , set track and sync to on
you probably want the transport/clock from hermod, so as to record notes properly.
so in ableton, make sure you don’t have any other midi clocks sources, other than hermod which you set up in 4. (=sync option)
press EXT on ableton, to link clocks
then its simply a matter of setting up a midi track for each hermod track, using midi channel
arming tracks - press play on Hermod.
to import to hermod, basically do the opposite, by using the standard midi FX on hermod, setup hermod tracks with different midi channels (I think you then need to change prefs to record multi channels)
note: when doing this, you probably want to shift ableton to be the master clock (though that’s not required)
you can probably do loop recording, but i think that may be limited to one track at a time (not sure, would need to check )
anyway - not an extensive guide, but hopefully enough to point you in the right direction.