Setting the Applies To property of conditional formats can be a task in which Excel's CF Manager dialog box quickly reaches its limits of usefulness. The answer is to list all existing formats and then refer to this list while making modifications in the CF Manager.
Simply drag the CFman code module from the attached workbook to your own project and run the procedure ListCFs after setting the SourceSheet constant to the name of the tab you wish to examine. The worksheet in the attached workbook is only intended for easy testing. It isn't required in your project.
The worksheets the code creates can be deleted when no longer needed for reference.
The code in CFman includes the procedure LastRow which is required in most VB projects. If this is the case in your own project, replace all existing code requiring the last row in any column of any sheet with calls to this function with the appropriate arguments.