1. GWX is compatible with the steam version
2. Yes, there is a way to encounter carriers, task forces, and battleships sailing in and out of convoy... You get these by installing GWX
3. In stock, you will probably encounter seagulls and a beautiful view of the beachfront. With GWX - depending upon the year, port raiding may prove impossible due to sub nets, mines, blockade ships, harbor patrol craft, destroyers, shore battery, search lights, harsh language, knives, sharp sticks, rocks, etc.
