I have installed this plugin in our new WordPress installation. It looks great. With only posts from 10/2010 till 02/2011 it turns out that in the [ioya] generated page the links to next and previous years do not work,
because the link to the current month in the previous/next year and if that month does not have posts, the link does not function. I have patched it with 01 for the month in next year link and 12 for the month in the previous year link, works for now, but it may not be the real solution. If guess you must search for the first month with posts in the next year and the last month with posts in the previous year.