I bought my CR-6 SE printer in the fall and had a need to do some out-of-the-box printing straightaway. While it worked for the small footprint objects I was printing, the Z-axis homing and offset was inconsistent so I had to be careful about rechecking between every print. After searching about this phenomenon I came across this forum thread and it seemed to address what was by all accounts a firmware upgrade need.
After studying the thread thoroughly I finally got around to doing the firmware upgrade. I have to thank all those who came before me working out the kinks in the "documentation" and process; as they say, "standing on the shoulders of giants". I used the 8 GB SD card (reformatted to 32K to 4K allocation size) that came with the printer to perform the main board firmware update. I managed to scrounge a 4 GB microSD card (also reformatted to 4K) for the display firmware update. Both worked the first time through the upgrade process. As indicated in a number of places, I do wish Creality would be more consistent in labeling the firmware package version information.
Now the Z-axis homing and offset are consistent, at least as many times as I rechecked it from various random offsets.
I also had to perform a Z-axis bed leveling to take out the skew across the bed. I found a video that indicated loosening one of the Z-axis pulley screws at the top and tweaking the lead screw will adjust the gross Z-axis offset across the center of the plate. The adjustment was a little tedious but doable and I got it very close by eye. It's a little off along the front and back edges of the plate, but now I hope the auto-leveling will have an easier time compensating for fine adjustments.
Thanks for al the information and experience provided in this thread.