How are you connecting the Motif to Logic? Bear in mind the USB connection is only for Midi and not for Audio so you will need to connect the Audio outputs of your Motif to your Mac via either the built in audio input or an Audio Interface to hear/record the audio via/into Logic.
So, first steps...
Does the transport bar show midi info when you press keys on your Motif..
If so.... You should be able to simply create a software Instrument track, select a Software Instrument for that track,... and then play your Motif to play notes via that Software instrument... have you tried that to make sure your Motif is sending Midi correctly?
Now, if you want to hear your Motif's own sounds and record them instead of using a Software Instrument...
Here is one way of achieving this..