The author has a note up on the plugin homepage saying that the plugin is no longer supported.
Support & Bugs
Support and feature requests should be made through the Advanced Permalinks support forum. Due to time constraints I will no longer answer questions about this plugin myself. You are advised to make use of WordPress 3.0 and custom post types.
I’m attempting to get this plugin working again on 3.1.1, but no promises. Permalink Editor is an alternative, but I haven’t been able to make it do what I need.