Just passing on what I've found so far for those who are interested in designing for 2004.
FSSC still works fine BUT I've found that 2004 is much more sensitive to heights (scenery height ASL, polygon heights etc). AFCAD2 can't yet change the airport ref point in the AFD file so if your scenery is at a different height than the default you're replacing, you'll find that you lose things like the progressive taxi line which can disappear below the surface.
A16-N flattens work fine but again you have to get the height right. I found that sometimes my flatten bgl didn't automatically export from FSSC and I manually had to compile (using SCASM) the flatten sca file and copy across the resulting bgl. Don't know why yet my copy of FSSC should be doing that.
I cannot get scenery changes to show in the sim unless I fully deactivate and delete the scenery from the scenery library and sometimes even the corresponding bgl files plus the scenery.dat file from the addon scenery sub-folder. It seems to me that 2004 hangs onto the data harder than 2002.
In any case, you can't make ANY change to scenery without stopping and restarting the sim whereas with 2002 you could just click world..scenery library..OK to get a 'warm' restart. Not now though.
You may know that AFCAD2 creates lovely taxi lines and taxiway lighting for you. True, but NOT if you have put down your own apron/taxiway polygons ie the lines etc ONLY show up on top of original ground textures. Don't do what I did and delete all your lines and stuff (luckily I had a backup
)
I've got quite a few excludes in my scenery to remove unwanted original items but I don't yet know if they're all necessary because in a weird way, the replacement scenery seems to be working as its own exclude (ie bits of original have gone that I haven't actively excluded).
I've used LWM and CoastLineMaker and just copied over my files from 2002. Both still work OK in 2004.
Having problems with my AFCAD2 file. As well as the height problem mentioned above there also seems to me to be a parking radius problem. In AFCAD 1, ga_small only included planes like the 152, 172,182, Cherokee and Baron plus birds like the Mustang. It DIDN'T include the Caravan.
In AFCAD2 parking slots that I've designated ga_small are being filled by Caravans, ousting the smaller types. Also I've got Dash 8s going into Medium Gates whereas before they were in ga_large. It's more serious than it sounds - making it very difficult to get an AFD file doing what I want it to.
That's it for now. If anyone else is working in 2004 and has found other stuff that I've not mentioned I'd really like to hear about it.
You know ..... Fore-warned is Fore-armed
Roger
Edit added
Re AFCAD parking slots. It pays to read the manual! Radius has been downgraded a bit since 2002. Now there are other ways of designating spots which are far more powerful - plus you can specifically link aircraft to spots by parking types and codes in the aircraft.cfg file.