Importing issue Axure to Axure: folder structure breaks

Hi,

I have a complex file with a complex folder structure which I have to import from one Axure file to another Axure file. When importing, I get all the stuff in there, but the structure within the widget panel looks totally different and I always have to rebuild the folder structure. See the attachments “to be imported” and “imported” to see how it looks.

How can I get the same folder structure when importing?