Help me:Troubles using Fan Out and Fan Out All in Pro/Cabling

Hi,
I'm trying to make a flat harness with multiple wires attached to
multiple entry ports of a connector. I'm following the steps on
"Suggested Technique for fanning out flattened wires to connectors"
(by www.ptc.com) but when I select Fan Out the wires remain out of
the connector, and the message "Some wire/cable(s) were not fanned out
due to insufficient length." appears . I selected the shortest wire
and I even used the Assemble All command to attach each connector to
the shortest wire automatically… but it don't work!! When I made a
mistake? Does anyone have any advice on fanning out wires?
Thanks and sorry for my English!
Ciao
Pino from Italy.