Couple of newbie questions.........

[alowen]

Hi all, ive recently been bought sh3 and subsequently upgraded my pc's videocard to enable me to play it......WOW what an amazing game. I loved sh2 but this is awesome.
However, i have a few questions that are bugging me :

1) What are the different colour triangles for when using the periscope during an attack, they vary from green to red and orange ???????

2) When i select my uzo station the screen lags like hell and i have to shoot torps submerged, is it only for night use ????????

3) As it is the game seems to run fine, but for a newbie what mods should i consider first to make the game even better ???????

Finally , in sh2 the scream of alarm sound effect when crash diving was excellent, just like das boot, but in sh3 i can only get a rather sombre, "crash dive" announced. Can i get it to or upload the alarm scream again ?????

Thanks in advance for any help on these.

Al