I recently updated to Version 3.1 of the Tweet Old Post plugin. Previously Version 3.0 was working fine for me.
I can't get version 3.1 to manually or automatically tweet an old post. I've tried changing all of the settings and I always get this message now:
"No post found to tweet. Please check your settings and try again."
Again, version 3.0 was working for me. I would go back to it, but I can only find version 1.5 as a previous version available for download.