It looks as if the field TranslationMemoryAction.lastTaskResult (a Future) is always null. This class, along with zanata-war/src/main/webapp/tm/home.xhtml, needs to be cleaned up, because asyncTaskHandleManager's AsyncTaskHandle appears to be a replacement for lastTaskResult.
NB I don't think this is strictly a CDI cleanup problem, because it looks like lastTaskResult would be null in the Seam version too.