still dealing with MadCap Lingo, my colleague and I found ourselves in this scenario:
we tried to add a corporate xml file into an existing project or new project, and the screen below shows what was next:

it seems Lingo failed to properly load our xml file.
So, we tried out another way:
copy the xml file content > generate a new xml file > paste the 1st xml file content into the new one > name it differently.
After that, we repeated previous steps and finally could see the new xml file loaded:

(sorry for resolution)
Is there a reason why Lingo fails to load corporate/existing xml file?
Are we compelled to get into these steps to properly work with Lingo?
Our direct MadCap assistant/contact is not promptly answering emails (though considering time zone), that's why we're asking for your "assistance"
Thank you all!