After several activiations and deactivations due to reinstalls of the same Kobo Touch device, I now get the error Maximum Amount of Computers per Id has been reached. Apparently the activations are counted, but the deactivations are not extracted from the count. Now I can't transfer my library books to my device anymore.
As the support page directs I need to contact customer service to reset my account activations and that customer service page directs me to this forum. So please reset my activations as your support suggests, apparently I can't do it myself.