This is new. o_o
1) all user created meshes, materials, and textures should be in "my_objects".
2) if the mat still stays white, while the mesh is highlighted type in "leanto/TEXFACE/firBark.jpg" exactly like that upper cased and all. Then hit the "update button". The wood should change to normal now.
3)if not, re-download. something is corrupted.
4)if so, hit the little arrow above the mat and type "leanto/TEXFACE/thatch1.png" as the second mat to get the thatch to fix.
What drek does with her mesh downloads is very different from my means and her fix cannot be applied here. Usually typing in the mat name manually fixes the issue.