The procedure you followed won't work if the plist was already corrupted. You have to start with a clean duplicate plist. Your next option is to take screen shots of all your WC preference settings, close WC, delete the plist, trash it, delete the trash, reboot the Mac, and start over with initializing WeatherCat. When you know you have a clean install, then duplicate the plist so the next time this happens, you'll have a clean copy to use as a backup.
I don't know if you have a plist issue, but if you do, it has to be rebuilt from scratch unless you have a clean duplicate of the original. Alternatively, if you can restore the plist from a working back up using Time Machine, Carbon Copy Cloner, Super Duper, or whatever software you use for backups, then you won't need to go through the hassle of starting over.
Hope this helps.