I found a post on a forum which said that the FE team had made building sea walls and stuff in an earlier build and then removed the feature and it made me wonder: Could the data still be there? After all, Definitive edition had distinct art and data for sea fortifications, and lo and behold: The data was still there! Using 'Advanced Genie Editor' I found it easy to make the sea fortifications buildable from a fishing boat but was stymed by a problem: While I could go thru the motions of building, I could not establish a building foundation or make the fishing ship build anything except fish traps. Any ideas on what the problem could be?