[Plugin: Most And Least Read Posts Widget] Number of posts for last read doesn't save

Thanks for the plugin!
The “most read” widget works well. In the settings of the “last read” widget, however, the number of displayed articles is not saved and it looks like it always resets to zero, displaying no posts.
Also one idea for future enhancement: It would be great to restrict the display of posts by categories.

http://wordpress.org/extend/plugins/most-and-least-read-posts-widget/