Oh I see. If it's in a code box you can copy and past but if it isn't you have to drag it in. I was just downloading it, selecting all text, copy and paste, then I would get the error. I see the mess up now. Why would it be different? Sorry, I don't know how xml's or any sort of code really works.
If you compare the structure of the file you downloaded to a command group posted in a code box on the forum, you'll see a slight difference.
There's another hierarchical level in the exported file above the group level in order to accommodate the export of multiple groups of commands.
You could have actually copied/pasted the group xml into your tree by opening the file, but you would have had to copy just the command group xml rather than copying all the text.
But that method would be less efficient and is more prone to error than just dragging the file into the tree directly as per the instructions. So I would stick to the drag'n'drop method for exported command xml files.