iPhoto Migration to Lightroom

Hi, 

i try to migrate my iPhoto Bibs into Lighrooom, i have about 8 iPhoto Librarys from about 250GBb up to 1TB .

For the beginning i tried to import the smallest one with 238gb and the Import/Migration Wizard for iPhoto of Lightroom Classic validates the Library and i can choose new Destination Folder for the Lighroom Pictures. 

But I`m unable to start the Import Process because it tells me <unknown> amount of pictures.

Do you know if theres another Way to import the Librarys with related Albums and Description ? 

Regards
Leon