1st of all--Welcome to the site!
2nd: No need to rant. One of the reasons subsims have a small followitn is for the reason you pointed out--hours without action. That is a BIG part of the simulation atmosphere though as submarines could go weeks without spotting anything.
3rd: You're absolutely right about the manual--but there isn'y much they could put in there to help you find ships except: Go lay off an enemy port and wait. let the ships come to you--don't try to find them. If you pick a good spot off a major (or minor) port/shipping lane, they will be there.
When you set the radar to sweep--it stays that way until you go to the station again. It just stops sweeping when you go to the station so you have to click the switch to watch it.
My sincere advice: Hang in there!!!! You wouldn't be trying this genre of sim if you weren't interested. The hours eventually pay off--and in a BIG way!!!
I do understand how you feel though. After all--I was new to subsims once.
Also--Beware!!! When the action comes, you may get as hooked as so many of us already are
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