We developed a few landing pages using LP version 1.4.8. They worked fine under WP 3.8.1. I updated LP to 1.5.0, and all landing pages broke down. Reinstall didn't solve, neither entering to the component and saving settings. Was unable to save any new landing pages. The message was something like 'Notice: Undefined index: post_status'
Solution was to delete the plugin folder on the server and replace with a backup copy of 1.4.8