Here is a multiplayer map I made:
http://www.filefront.com/16649959/MP04.zip/
A lot of targets (take some time for loading).
If you want to use hydrophone I recommend the sub_hydro_fix (vicker_03 ?), otherwise the map could crash, because there are undine subs in the water.
I have played the map many times and seems to be ok.
Sorry for poor english.
Maybe you could tell me what you think about the map. I could rework.
Gruss aus Berlin.
Echol

t.