Hey Caesar !
I knew the method about adding the new maps in the "Terrain" folder. And you are right: for the recent maps it is said if it can be installed with WoV or not (most of the time the maps are buit for SFP and with luck they work for WoV).
About the complete method, you were right: I found some help somewhere in the forum and now I know how to replace the famous desert.cat by the VietnamSEA.cat file !
But I have to admit that since the game is not too recent I often see comments like "as usual" or "same method as previous mods" ... so for a poor newbie that was not easy to begin !
Thanks anyway for your help, CIAO !
Lipo