
Hiya Kevin, lotsa fun isn't it. Be careful you don't catch the bug - it's already too late probably

No there's no visual reference, you just have to experiment and use trial and error.
Yep, these are all the objects that are available to use. The spreadsheet in the SDK is MUCH bigger but trouble is that it includes virtually every object ever created by M$ back to the year dot, most of which aren't in FS9. Also, the SDK sheet includes many objects like buildings from default airports that are area limited - eg you can't place an object from KORD anywhere else except Chicago.
Actually, in my experiments I placed a Chek Lap Kok building at Kai Tak which shows there is a very small area of tolerance but to all intents and purposes 'special' buildings can't be used outside of their predefined areas (he he - no chance of placing the real Eiffel Tower at Las Vegas then :) )
So I weeded as many of em as I could identify out of the list - if I'd left em in it would only have created huge confusion I think.
But as I said to Bird, don't panic! The new MakeMdl SDK is about to be published and that'll tell us how to put NEW objects (probably GMax only) into the FS9 object library. Then the sky will be the limit.
Now you've learnt the principle using this little package you'll be able to go crazy - and with AFCAD and the XML skills you now have (OK, with one or two more maybe, but you've proved you can do it!) you'll be able to create sceneries that only the really experienced people were able to before.
Worth doing eh?
Glad that people seem to be finding the package useful
Roger