OK, i tested a little bit and i think i found the problem:
The Collection is imported as paused with the name "old"
Now i do a rightclick on the collection and select rename
Now i type the name "new"
Now i press Enter, the collection is unpaused and start downloading but is not renamed, the collectionname is still highlighted and editable
I have to click somewhere in the window and then the collection is renamed to "new". All the downloaded files until this click is in the folder "old" and all the files downloaded after this click is in the folder "new"
I think the alternative dialog will fix this behavior - yes, confirmed