Shortly after my post I found this Marlin site: https://marlin.crc.id.au/this commercial Marlin site 1). It offers firmware for crealityCreality & othersother printers. You can order 'off the shelf' firmware or customize it yourself. Customizing is quite easy & self explanatory.explanatory; 5 min. after submitting my requirements, I received a zip file, which I un-zipped & copied the needed file to my SD card. Then I inserted the SD card into my printer & started it. The printer recognized the new firmware & updated its self. This service is not free. Membership, $15.00/year, is required. See site for details.
1) This service is not free. Membership of \$15.00/year, is required.