Welcome to Subsim. I am glad what 14 year old game still gets new players.
I will try to answer your questions
1. I am not 100% sure, but I think text over torpedo is multiplayer feature.
2. Have you installed this
http://www.subsim.com/radioroom/showthread.php?t=147567 its required to install this. In order to play GWX WITH COMMANDER.
5. You can change starting date of the campaign in commander program near the flotillas.
What's your mod list? JGSME