How can I link the Texture Type output (material Assimpt)?

I can´t link the Texture Type Output in Material (Assimp) to any node, so I have to use file texture node to view it. The ouput gets only an enumeration (nil), but the inspektor says that there are 2 textures: diffuse and bump. What am i missing?
Maybe the isn´t any texture in material node?
Thank for the help

Material assimp.7z (15.4 kB)