Help creating a custom tile material

Thank you Dave,

Did you notice the single tile that I modeled with radius edges? It has a small open section where I drew the initial arc to be used with follow me to create the radius top surface. I tried to erase the edges but that caused entire sections of the face to disappear. Is this being caused by arc lines not meeting the edges exactly?

Would I use gimp as my file editor in your example above? Or is that image features referred to here “I exported the image as a PNG and in Options, I enabled Transparent Background. In the image editor, the image opens looking like this:” native within sketchup?

What dimension are you referring to when you say:

This texture would be applied to several walls within a room that have irregular dimensions.

In response to the grout coloring, I don’t know what I don’t know so I end up going down the wrong path.

Rick