If your goal is to get pictures out of FT that you never want to work with in FT again (that is, a one-way workflow from FT to other tools), try File>>Save As with an appropriate image type. This technique will save the current FT view to an image file that you can edit or annotate using tools such as the GIMP.

Contour maps can be exported to CC3 using File>>Save Campaign Cartographer File.

An easy way to separate the land and sea to allow for applying coastline effects is to modify the altitude shader so that the land is white and sea is black (Map>>Lighting and Color, Altitude page). On the Intensity page, set Shadows to None and you'll have a mask that's white where there is land and black where there's water. This mask can be used in the GIMP to separate the land from the sea.

In FT3, ice caps appear in the climate shaders. The regular climate shader shows solid colors. The Image Climate shader was updated for FT3 to include an image for land and for sea, allowing ice caps to flow onto sea as well as land. The Textured Climate shader is new for FT3 and allows swatches of textures to be repeated across climate types (works on both land and sea).