The programmer for WP-UI has created one of the nicest add-ons for wordpress around. Making it possible to break down large, complex documents into Tabs and "spoilers" that allow a guest to quickly see the content.
Sadly the latest upgrade has left the spoiler option badly damaged, and after two months has failed to repair it, leaving older users who were relying on this option, with badly damaged blogs, in some cases like mine, causing major PR disaster and loss of support.
This is a warning to people. One of the major parts of this plugin is currently broken.