There is a small tool exactly for this purpose called TranslationUpdater. The installer is included in the Control plus bundle download in the folder Common\TranslationUpdater\V1.5.
With this tool, you can specify a folder with object definitions, and it will generate a .uni file (same format as the tranlation export from CpStudio) with all the texts missing a translation for a given language.
After completing the tranlations in the .uni file, you can use the second tab page of the TranslationUpdater UI to merge the translations back into the object definitions.
In case you are adding translations to objects provided by BCI, we recommend you to send us the result, so we can integrate the translations into the next official object version. That way, you don't need to merge the translations again after updating to a new object version from our server. Please contact the HelpDesk in that case.
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