I have a short single mission uploaded here:
http://rapidshare.com/files/89190426/minelayer.mis.html
You need to go a good distance NW to actually intercept :p just like a good schnellboote should!
Here is a screenie of one of the hits:
Be gentle with criticism about the mission; it was very fast and dirty, just to give people a little taste of playing the S-boot under reasonable terms.