How to restore a Helium backup?

I am transfering to a new phone, and I backed up my stuff using helium to Dropbox. Later I copied that folder to carbon folder on my sdcard, but helium doesnt seem to detect it. Any idea how I can restore that? It looks like the format is different.. Regular backup seems to be carbon/com.appname/files but in my dropbox backup, its only files, no folders at all.