I created a 'shared' spreadsheet and made cells containing different
backround & font colors (say, white text on blue background).

The problem is, when someone else opens the shared spreadsheet, they see
different colors than what I've created.

This is especially problematic in the following scenario:  MY workbook shows
white text on a blue background, THEIR workbook shows Green text on Green
background (so the cell APPEARS to be blank, until you click on it to look at
the actual cell contents).

Not sure how to get us all on the same page in shared workbooks.