When exporting using an existing Excel file all formatting is preserved (column width, row heights, cell formatting, etc…) The only thing that isn’t being preserved is the conditional formatting.
When EnableStylesExport is turned on (True) the conditional formats are not in the file; however, the Excel Exporter did create some styling in the file as its default.
Attached is a zip file containing the source file (template) and 2 ouput files based on the EnableStylesExport value.
Version: 12.2.20122.2075
The Excel library does not currently support round-tripping conditional formatting information. I have forwarded this post to the Developer Support Manager to create a feature request on your behalf.
Thanks!