If you dont have 64 bit system and 8 gigs of ram then the game might run out of memory .
1/ Anyway , you are using open horizons 2 mod so read the special instructions on starting a career with OH2 .
http://www.subsim.com/radioroom/showthread.php?t=180044
2/ Look for the shadow improvement mod lite . Its in the magnum opus mods folder i think . The standard one uses too many resources . Put your shadows slider to halfway in the ingame graphics options .
3/ You need my sobers realistic underwater FX2 SH5 mod .
http://www.subsim.com/radioroom/down...o=file&id=2750