Just to clarify, there are two issues relating to Slidebook 5.5 support, as Melissa mentioned above:
http://trac.openmicroscopy.org.uk/ome/ticket/9933
http://trac.openmicroscopy.org.uk/ome/ticket/10473
#10473 is fixed, which allows Bio-Formats to recognise the files, but #9933 is still outstanding, so they can't yet be read properly. This will be completed in due course, but at the moment it's not fully supported.
Sorry for any confusion caused here.
Regards,
Roger