I am working to use YARG as report generator in my application. We really like the support of formula and pivot table in the excel format, and the functionality to convert to pdf report. The only thing we find a pity to lack is that the pictures in the excel template header (for printing) will be lost after conversion to pdf, because Openoffice has a different way to implement graphics as the header. This function is often needed for logo printing. Is there a plan to implement this?
Another way to look at it is perhaps to support OpenOffice format directly as template.