When the data is missing the program just complains about a missing file and exits

It shows the message ```"Couldn't load montlake (in seattle (us)) No such file or directory"``` with the Ok button and exits.

It should suggest the user what to do. Otherwise the behavior looks like it is broken.

Look for the error message 'Couldn't load montlake (in seattle (us)) No such file or directory' in the codebase to find where file loading fails. The fix involves improving the error handling to suggest user actions, such as checking file paths or downloading missing data. Test by running the program with missing data to see the new helpful message.

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