~S~ Spit
You don't really need scenery for mp carrier work - you need to swap to a mission with carriers in it.
First get hold of and install MPSU -
http://www.airwarfare.com/Sims/CFS2/essentials.htmThen go get your carrier missions. Carrier Haven and Shipyards are the most widely used - these have static carriers in them. You can also find ones with moving carriers in (though these can cause difficulties if players join the session late - they see the carriers in different places to the players that joined at the outset)
Use MPSU to set you allegiance (Japanese or US) then swap to the mission your require. Minimise but don't close MPSU and then join the multiplayer game. Everyone who has swapped to the same mission and joins your session will see the same mission objects.
BTW - you can get the missions I mentioned here (amongst other places):
http://www.spikespage.com/downloads/required.html~S~
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