There's an ancient error that seems to still occur occasionally: When attempting to delete individual control pts on a path, the entire path is deleted. I would typically consider any odd behavior like this to be corrupted prefs. (and maybe it still is) I recall this occasional bug going back many versions. In today's case (using CS5 offsite) the error was repeatable in the same file consistently, with any path, including new paths. This persisted even after computer reboot. Yet it did NOT occur in new files. I'm using CS6 at my own studio, and have not had the problem yet, but this has occured only occasionally over time. I really dislike resetting prefs ever time there's an oddity.