I think I have an other way for you!
Go to Window- Rendering editors- Hypershade.
There you can make new materials. ( only drag and drop the Material you choosed ( on the left side ) in the upper window. (There is the default lambert too. )
Double click on your new material and you can add some textures or what you want. In that scene you have now different materials for your models.
To texturise you must only drag and drop from the Hypershade window with the middle mouse button to the object in your scene.
That way is better for your workflow. Rename all materials you made( right mousebutton on that material in Hypershade- Rename )