Mission Planner’s latest version is 1.3.80. You should probably update to that.
4.3.0 is the Arducopter firmware on your cube. You should also update that to at least the latest stable (4.3.5) since I understand there’s been some updates for the Cubes.
If the compass was calibrated why are you doing it again?
My suggestion, is once you’ve updated your firmware and software is to try and do a basic calibration again, outside with a good GPS lock and away form interference. Don’t worry about how “good” it is, just get it done. Then once you’re flying run Magfit and update your parameters based on that. Then forget about it unless you change parts or move something.