MerseyJ
You are correct in your assessment, it is a single all round red light for the carriage of Hazardous cargo - the reason that it is in the fore part of the vessel is that she is forward accomodation. The Christmas tree (as we call it, lots of different colour lights) is near the forward mast on most ferries.
The all round red light for carriage of hazardous cargo has never been accepted into the collision regulations, but I believe that the port of liverpool has a local byelaw. Hazardous cargo is more common on ferries than you would believe, almost every crossing we have between 2 and 6 units of hazardous cargo. The usual ones are UN1950 Aerosols (Class 2.1), Carbon Dioxide (Class 2.2), Batteries (Class
, Straw (Class 4.1) etc etc, there are so many out there - even perfume and concentrated Coca-Cola are hazardous - Coke being a Class 8 corrosive!!!
Hope this helps,
Steve