Looking nice, but have you considered some kind of coastline effects on your map, there is a very sudden jump between land and sea, nothing that provides a transition. Often a simple outline or glow is enough.

Well, as the Tome itself states in the introduction, it is written for intermediate to advanced users. It does assume some knowledge of the basics of cc3+, and relies on the user having worked through the tutorials in the manual first, and probably worked a bit on their own before diving into the Tome.

Also understand that the tutorial is written for that particular map in mind, it is extremely difficult to figure out all the ways a user may want to do things differente from the tutorial and reference those, that would also make the tutorial extremely bloated. The goal of the tutorial is to teach the user various techniques based on the requirements for that map.

Are you selecting the lines correctly? I just did a quick and dirty import following the steps in the guide, and I had no problems trimming the entities.

However, what can be confusing when doing this is:

• The Rivers/Roads when exported from the Watabou site actually consists of multiple lines on top of each other. CC3+'s trim tools work on one line at a time, and even if that line has already been trimmed, it is still a valid line so you can end up basically trimming the same line multiple times, which doesn't really give you any progress.
• Remember that thick lines are still selected by their centerline (this is where the actual line is), not by the edge as a polygon would be

The tutorial in the Tome expects you to draw it as the image, which do have a gap on the east side (It's not visible there, but there are more islands to the east, which is why the water is less deep there).

If you need it to go all the way around without a gap, you'll have to use a multipoly to achieve that.

The tutorial files for the tome should be installed to your CC3+ data directory (You chose the location of this during the install, default is c:\programdata\ProFantasy\CC3Plus), referred to as @ in the documentation and CC3+ itself. Look for the subdirectory called tutorials located here.