Note, that if you are running your Product Guide with a Language you do not have created yet localized columns for, the Product Guide will automatically fall back to the original default column.

Example:

You have prepared your Product Data with a default column "description" with English texts and an additional column "description_de_DE" for German texts and you use the field "description" as a Display Attribute.

When running your Product Guide now with German (de_DE) it will automatically use to the column "description_de_DE" 

When running your Product Guide now with French (fr_FR) it will automatically fallback to the column "description" (as no equivalent column for French could be found).