Solved. Possbily for someone's future reference. Using a computer, mixer and DAW to record is about as frustrating as trying to update software on an old Ultra through Midi. I was able to record a drum track in Studio One 3 and get play back. Major achievement. Then I re-opened the file anew, the track was greyed out and I could not get audio. Now when I am trying to open a new song and lay down the drum track again, I can hear the drum machine through my monitor but there is no signal going into the DAW. My connections are 1) Focusrite USB to computer, Focusrite RCA to Tape Input on my Mackie mixer, 2) SR18 drum machine R output to mic in on Focusrite with XLR cable, 3) AXE II out 1 to guitar in on Focusrite, 3) I am unsure whether or not I need to have the audio jack on my Dell laptop connected to mixer.
While typing above, it occurred to me I might have an incorrect USB setting. Although my audio was set to Focusrite driver, one of those little hidden icons on the bottom right tool bar need to be clicked. When I did that I saw the wrong audio device was selected. Changing to Focusrite solved it.