I see absolutely no need to "export" an SDLXLIFF file. Just send the translated file to the agency.
Hans Lenting: For novice users this drilling down into the folder structure can be difficult.
The novice user as mentioned on ProZ knew how to "drill" her way to the SDLXLIFF file to be translated, so I reckon she can find it again.
Do not make things more difficult than they are.
Rather than being tolerant, we should provide the correct information. Exporting an SDLXLIFF file as a CT package is not the right procedure. Not even if you change the extension into *.zip. Poor newbies. It's madness. If not one step beyond madness.