Check and see if R55 is installed on the bottom side of the board, right under one corner of the FPGA. Some boards went out with this part installed and it will sometimes give the user the message "JTAG error. Unable to download firmware". If this part is present, just remove it and the problem is usually corrected. If you would like us to remove it or provide you with another board, let us know and we will make arrangements to take care of this.
Regards,
Jim