Dear GunnarKj:
I have worked before with Canopen. It is a very powerfull network, and also maybe a little complex, if you are just starting to work with.
Basic applications as reading inputs and writing outputs are eficiently handled, using event messages.
More complex tasks, for instance controlling the position of a servo is done sending the position each cycle, then is possible to do it in cyclic mode.
I would like to help and guide you, and may need more information of your needs. You may reply here or write me at fguedez at cantv.net.
Best regards