Hi Ken,
Thanks for your update.
Support for Stacked Multiheaders was introduced in 5.1.0.51 version. Could you please upgrade to anyone of our latest version, so that you can get it?
You can download our latest version from the below forum link:
'>http://www.syncfusion.com/support/Forums/message.aspx?&MessageID=72983"> http://www.syncfusion.com/support/Forums/message.aspx?&MessageID=72983Please let me know if you need any further assistance.
Regards,
Subhasheela R