Después de casi un año desde la primera incidencia, responden.

Hi RaveN-

This should be all fixed for you know. One of your set
descriptions had an invisible ASCII character that was
“damaged” and causing the Flickr API to fail when trying to
access the set. That character was removed, and all your
sets should load properly now.

Thanks for your patience, and sorry it took so long to
track it down.