To answer some of your other questions:
Red Eagle is the one ship that uses Voith-Schneider propellers. There are many posts, and a lengthy topic on the VSP. Here is that topic:
http://www.shipsim.com/ShipSimForum/index.php/topic,2550.msg26287.html#msg26287 (http://www.shipsim.com/ShipSimForum/index.php/topic,2550.msg26287.html#msg26287)
In addition, INFO.pdf and the Mission Editor tutorial give additional instructions for maneuvering Red Eagle:
http://www.shipsim.com/ShipSimForum/index.php/topic,2886.0.html (http://www.shipsim.com/ShipSimForum/index.php/topic,2886.0.html)
The UI controls for a ship are often very similar to those on the bridge, but there are often differences in size or appearance. The biggest difference is perhaps in Titanic, where the Engine Order Telegraph is replaced by the simple throttles.
The jetski has a wheel in the UI.
I don’t bother with MP, so someone else can answer, or you can just read posts in the Multiplayer section, if you can access it. Lag is a serious problem, depending partly on your connection speed.
Marty