@ShagMeister - welcome to MobileRead. In terms of your error, it isn't clear if you are actually following the directions. Read the Help file for the plugin if you are unclear - clicking Authorise should open a page in your web browser requiring you to log into your Goodreads account and authorise the calibre plugin. Have you actually done that? Since it is working for Janet54 above there isn't anything wrong with the plugin code, it may well have been either you didn't complete the sequence or Goodreads was having one of their temporary glitches. Just keep trying and if the problem persists contact Goodreads support.
@Gunnerp245 - glad it is working again for you as expected.