Assuming that the textures are in jpg or other bitmap format, save them to the DataCAD Textures folder and then create the materials in DataCAD using the edit materials function.
You can edit one of the materials included in DataCAD and save as a new material. You will need to try different scaling values to get the siding textures to the correct scale in DataCAD.
James Goodman, AIA
Capistrano Beach, CA
Since V2.5f (1985)