Thanks for the welcome and helpful info

I've advanced to a Type VIIB and what a beut she is - loads of torps and finally a deck gun.
I haven't been depthcharged at all yet besides the odd Hurricane coming in (much too fast and with wonky flight modelling). Thus far all my attacks have been at 90 degrees and inside 1000 m, usually between 500 and 700 m. Can't really miss then, though I had one GII torp spontaneously combust in mid run. I've found it exceptionally easy to intercept and set up attacks, especially after noticing the Lock feature hehe.
Still waiting to experience a full-blooded convoy battle.
Now some Qs: torp speed, I suppose the settings S, M, F means Slow, Medium, Fast? I've been using the default setting (S) with run times at 40-65 seconds, and that seems fair enough.
Transfer - I'm in 1st Flotilla still (Feb 40) and I guess if I should go somewhere it's off Ireland? I haven't had the nerve to pick up the phone yet to see what will happen! hehe
Shallow water - depths of 30 m seems kinda risky should I get ganged by DDs, yes? I miss a seabed topo map.