You can't directly set a material with a Datalinq path using visual logic. The Object's face block needs a [Material] value, but the Datalinq path is a [String] value.
Instead, you can use Dynamic Materials to assign a @textobject@ macro value to your object face, and apply any Visual Logic you need to the text object referenced in your Dynamic Material Path.
Depending on the logic you're trying to accomplish, you might be able to do all this in your Dynamic Material path by including using your Text Object to be part of a file path, and setting it to something like C:\Users\Me\Pictures\@Text1@.tga
------------------------------
Jeff Mayer
Ross Video
------------------------------