First, thank you for this plugin.
I'm working with WordPress 3.5.1, and when I activated debug option I saw some warnings. Another problem I saw, was that the localization didn't work.
I've corrected all debug warnings (changed deprecated functions for the new ones) I've seen and the localization problem.
It's possible that, with my modifications, the plugin doesn't work with WordPress versions previous to 3.3.
Finally, I've updated spanish translation file.
You can find all my changes in my dropbox file: add-local-avatar-11.2.1.zip