In the strings.en-US.xls that ships with the application, only columns A (String Name) and B (String Value) have values in them. These are names of the string resources that the application uses, and the values which are used in place of those string resources when the pages are loaded. There shouldn't be anything in any other columns.
For multi-locale configurations, you should create additional files named strings.locale.xls (eg. strings.fr-FR.xls, string.es-CR.xls, etc...) that have the same 2 columns. Column A should remain the same (eg. account.aspx.25 would be account.aspx.25, etc...) and column B should be the translated version of the value (eg. Yes in strings.en-US.xls for account.aspx.25 would become Oui in strings.fr-FR.xls for account.aspx.25). You then create the locale fr-FR in the admin section and upload the strings.fr-FR.xls file for that locale, as outlined here in our manual
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