The SoftStep has multiple MIDI ports that change depending on whether you are in Hosted Mode or Standalone mode. Hosted mode is only available if you have the SoftStep Advanced Editor open and it gives more functionality but can also make things more confusing because you then need to configure your DAW to ignore the SSCOM port.
In your case you can set your SoftStep to Standalone mode and not have to worry about that step. You will need to understand how Logic handles MIDI controllers, for more info on that please refer to your Logic user manual. If you want to have the SoftStep control an instrument make sure you select the SoftStep SSCOM port in the MIDI settings on that track.
To use the Logic transport demo included with the SoftStep Editor, make sure that your SoftStep is connected to the editor, then change to standalone mode, then add the Logic preset to your SoftStep's setlist, and hit send. Now on your SoftStep hit the right button until the display name reads LOGC.
If your Logic App is able to receive MIDI from the SoftStep then it should get the MMC transport messages sent by the SoftStep.