A roundabout solution which will work on the shortterm ... why don't you convert the file back to 2003 on a second PC or Laptop, do the graphs and then copy & paste into the necessary Word document. There is a free program that allows you to do this ... do a google on "Batchwork Batch XLSX to XLS Convertor".
Ok, I know thats bypassing the main problem but it would allow you to get the graphs done.
By the way, use Dropbox if not doing so already - it really helps you to sync work between two PCs/laptops and allows sharing of work.