See? Perfectly reasonable, even with a bug report that can be actioned, no need to get upset
The last 1.x release is available from
http://download.calibre-ebook.com/1.48.0/. If you want all available calibre releases, you can go to
http://download.calibre-ebook.com/.
You'll probably want to disable update checks until your bug is fixed. Open 'Preferences', choose 'Behaviour', and un-check "Show notification when new version is available". Click Apply, and you're done. Just don't forget to check back periodically to see if your bug is fixed