What I'd entered: --coastlinefile coastlines_europe-111004.osm.pbf
It might be a worthwhile improvement for mkgmap to notice dud syntax like that and either accept the form without the '=' sign, or to put up an error message. As it is, it *seems* to realise that the coastline file is as I'd flagged it, but then reports that it can't read such a file. Confusing.
The message is confusing, granted, but all that is happening is that coastlines_europe-111004.osm.pbf is being treated as a map to compile. The coastline file is the empty string because no argument was given. So when it says: coastlines_europe-111004.osm.pbf: Coastline file not found It means while processing the map 'coastlines_europe-111004.osm.pbf', the coastline file '' was not found. ..Steve