Hi there,
I did some research for CANopen OpenSource libraries and found the canfestival.org. That seams to have a very active community. canfestival also supports already AVR chips as noted on their "supported devices" page under CanFestival documentation.
I saw all the work you have already done for supporting CAN on the due. Great work, amazing.
Do you think it is feasible to integrate the canfestival into the Arduino IDE for Arduino Due and possibly also in Arduino Uno with the seeedstudio or sparkfun can shield?
Thx