pieusb: Perfecta DigitDia 4000 does not advance slides
The flag "advance slide" does not have any effect on the Perfecta DigitDia 40000 scanner, although the device would be capable of slide transport. If you enable FLAG_SLIDE_TRANSPORT for the device in the pieusb.conf, scan will not work anymore. Disabling CMD_17 and enabling FLAG_SLIDE_TRANSPORT would result in a correct working device.