I noticed that the error messages, like the below one, remain untranslated:
"Error: Unable to select a template! Please make sure the following conditions are met:
there is at least one issue published and it had assigned valid templates for the front, section and article pages;
a template was assigned for the URL error handling in the publication configuration screen."
It would be very important to add them to the language files, because from localization view they are as important as the translations of the controls, or even more important, because when a problem occurs, the user gets stuck due to anguage problems.
The difficulty here is that because the publication is not working, it is harder to guess what the appropriate language for the error message might be. We might be able to use browser detection here.