In SPlat, I simply re named the Tungsten theme and then edited and saved. No problem.
Now in CbB, my edits turn the new piano roll view half white and half black. I do like the new look. Tried to change the white horizontal lines to the lighter dark shade as is in the new roll, but couldn't find the name of the horizontal lines in the editor. The black keys horizontals were unchanged. Very strange. Any suggestions? Thanks, Paul
 

They changed the Tungsten theme so you will need to copy the original from the SONAR themes folder to the CAKEWALK themes folder. 

Are you actually referring to the Horizontal lines? For the horizontal lines the white keys are the "Grid Background" under Piano Roll View, but the vertical beat indicators are "Grid Rules" under global and "Beat Rules" also under global

Yes, my mistake. The horizontal lines. And the "Grid background" is what I'm looking for, thanks.
 
And Johnny V, thanks. I have all my themes copied there.