Issue with Import-NAVApplicationObjectLanguage

Don't really know what's going wrong here. I'm working on a US localization of a HUGE add-on (more objects than standard NAV), trying to use as much Powershell as possible. To minimize differences, I exported all non-ENU languages, with the intention to import them back in after merging the objects. I used the Export-NAVApplicationObjectLanguage command to create the language files, and Remove-NAVApplicationObjectLanguage to delete the languages except the ENU one.

After finishing the merge, I want to import the languages back in using the Import-NAVApplicationObjectLanguage command, but that gives me an unhanded error message that I don't understand (see below). Now I would get if the language files would depend on specific line numbers in the text files that would get screwed up by the merge, but I am getting the same error message on the original object files.

Even the object files that I exported the languages from will not import the same language files back in.

What do I need to do to successfully import language files back into my merged objects?

WARNING: UnhandledErrorMessage
Import-NAVApplicationObjectLanguage : Illegal characters in path.
At line:1 char:1
+ Import-NAVApplicationObjectLanguage -Destination C:\Tempie\Target\*.txt -Languag ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:) [Import-NAVApplicationObjectLanguage], ArgumentException
+ FullyQualifiedErrorId : System.ArgumentException,Microsoft.Dynamics.Nav.Model.Tools.Cmdlets.ImportNavApplicationObjectLanguage