I have to refactor how that error shows to make it more understandable.
The problem is that the Free Google Translate tier can only handle so many translations per hour/min. So, when translating large databases or querying too often, it gets to the limit.
You are still able to use the WebService to Import/Export from google, but no translation, sorry!
One way to deal with this without having to wait, its to Export your language source to a google Spreadsheet, and place a "=GOOGLETRANSLATE(.....)" formula in the column of the language your want to translate. That will get all the translations without dealing with the Translate limit.
Then, Import back to Unity, and you will get everything translated.
Once I release this next version I will move into tweaking the translate to avoid this limit, by actually using the batching mode. In the current I2L I implemented a batch mode for translations, but I haven't still used it for the editor (just for the runtime).
Hope that helps,
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