Ok, I think it's an issue with putting carriers or carrier stations on the map, in the TARGETS.INI or something. If I place a unit at a ground base, it will show up...
From TARGETS.INI
[TargetArea233]
Name=Echo Station
Position=420000,800000
Radius=5657
ActiveYear=0
Location=12
Alignment=FRIENDLY
CarrierStation=TRUE
[TargetArea234]
Name=Marine Station
Position=425000,780000
Radius=5657
ActiveYear=0
Location=12
Alignment=FRIENDLY
CarrierStation=TRUE
And I added a location #12 in NATIONS.INI
[Theater]
TheaterName=Middle East
Location001=Israel
Location002=Egypt
Location003=Syria
Location004=Jordan
Location005=Lebanon
Location006=Saudi Arabia
Location007=Iraq
Location008=Sinai
Location009=West Bank
Location010=Gaza Strip
Location011=Golan Heights
Location012=Mediterranian Sea
[LimitedNationList]
FriendlyNation001=USN
FriendlyNation002=USMC
FriendlyNation003=ISRAEL
EnemyNation001=Egypt
EnemyNation002=Syria
EnemyNation003=Jordan
What did I forget?
PS: The limited nations thing is not an issue as it is the same in CEurope terrain, and I have successfully added USMC units to those stock campaigns