A couple of noob questions
 

Sorry if these are obvious but hey ho - I'm new here.

What does radar actually do and how do I use it?

And does it give your position away to the enemy when in use?

Also I have the GWX mod so have a lot of the single missions, when I complete a mission successfully it doesn't seem indicate anywhere that its complete or give any kind of tonnage sank - does it not do that?

all here

http://www.subsim.com/radioroom/showthread.php?t=96026