Current sports layer renderer is broken already quite a while. This was/is based on Osmarender which has been obsoleted in March 2012.
As stated by @malcolmh on 2014-05-09 this should be ported to a more current renderer.
@roeger announced (2014-12-14) a new Mapnik/TileMill based renderer, currently hosted at roeger/openseamap-layer-sports, waiting for a Mapnik based tile server to be ready.
Current sports layer renderer is broken already quite a while. This was/is based on Osmarender which has been obsoleted in March 2012.
As stated by @malcolmh on 2014-05-09 this should be ported to a more current renderer.
@roeger announced (2014-12-14) a new Mapnik/TileMill based renderer, currently hosted at roeger/openseamap-layer-sports, waiting for a Mapnik based tile server to be ready.