Nah i will give it a try with placing some actors, inside the meshes with relative locations and let the player move and check if its working this way. For the moment i need some time to create the meshes with vertex colors for the textures.
First, i was thinking about a big landscape with world composition, but i got problems with painting the textures. Because the landscape would be very large and if i understand it correctly - more components in the terrain are much more expensive.