Prewar versions would be from PBY-1 (1936-37) up to PBY-4 (1938) and didn't have a retractable gear. They had a fixed / attachable gear to be able to roll them around on the ground, but that was not intended to be used for taking off.
Retractable gear was only the PBY-5a (1941-45) and PBY-6a (1945). The letter "a" denoted the retractable gear in the type designation.
Aerosoft modeled the PBY5, 5a and 6a in their package.
I seem to remember that there was a colorful pre war livery somewhere, but I have to check that when I come home. That livery would be fictive on a PBY5, though.
I really admire the work that has been put into the Aerosoft version. There are even torpedo carrying models, a fully functional Sperry autopilot, a non standard (damage modeled) engine module, and a ton of other stuff that make flying the Cat a nice and challenging experience.
The only additional thing I would have loved to see is the flight engineers place in the center wing supporting nacelle (of which I'm not sure if it was still there in the latest versions) and the sea radar to go hunting for the Tokyo Express at night or bad weather
Cheers,
Mark