Layers Library
Layers are explained in the manual, read here.

Noaa buoy position layer based on a script that parsed the NOAA data. gpx file

UK Met Office forecast areas made manually with tracks and waypoints. gpx file

Some offshore wind farm areas. A kml file converted with gpsbabel. gpx file
Much more on this site www.justmagic.com/GM-GE.html
Note that far from all kmz/kml are suitable for conversion. gpx file
Chart Corrections
Navigation marks, lights and AIS beacons.
AIS Beacons in the British Isles and the French West Coast
List of Lights
Offshore Wind Farms
Windfarms 1
Windfarms 2
Platforms
Platforms
Traffic Separations
TSS zones
Weather related
NOAA wx-buoy positions.
UK forecast areas.
French Atlantic forecast areas. Updated 2012-12-19.
Wrecks
Some Wrecks
Exclusive Economic Zones
Africa and West Asia.
Antarctica
Australia.
Canada.
Central America
Dutch Overseas Territories.
Europe Northern Part.
Europe Southern Part
France North Atlantic area.
France Mediterranean area.
France Overseas Territories.
Norwegian Overseas Territory.
Pacific Islands
Russia
South America
South and East Asia
UK and Channel Islands.
UK Overseas Territories.
USA including Overseas Territories
Some examples to start the library and the discussion.

Noaa buoy position layer based on a script that parsed the NOAA data. gpx file

UK Met Office forecast areas made manually with tracks and waypoints. gpx file

Some offshore wind farm areas. A kml file converted with gpsbabel. gpx file
Much more on this site www.justmagic.com/GM-GE.html
Note that far from all kmz/kml are suitable for conversion. gpx file
Chart Corrections
Navigation marks, lights and AIS beacons.
AIS Beacons in the British Isles and the French West Coast
List of Lights
Offshore Wind Farms
Windfarms 1
Windfarms 2
Platforms
Platforms
Traffic Separations
TSS zones
Weather related
NOAA wx-buoy positions.
UK forecast areas.
French Atlantic forecast areas. Updated 2012-12-19.
Wrecks
Some Wrecks
Exclusive Economic Zones
Africa and West Asia.
Antarctica
Australia.
Canada.
Central America
Dutch Overseas Territories.
Europe Northern Part.
Europe Southern Part
France North Atlantic area.
France Mediterranean area.
France Overseas Territories.
Norwegian Overseas Territory.
Pacific Islands
Russia
South America
South and East Asia
UK and Channel Islands.
UK Overseas Territories.
USA including Overseas Territories