Thanks aaronil, glad you liked those! And yes, of course...use them as-is, mod them, or whatever you want.
This is how I altered your tiles/moss in PSP8. With the base tile, I changed the Brightness to -30 and contrast to 35. Then Shadow to 35, Midtone to 25, and Highlight to 15. Then laid the moss on top and changed the layer to Multiply with an Opacity of 60. Then the Blend Channel: Grey Channel to This Layer 38. Then duplicated the moss layer and changed it to Darken with an Opacity of 60. Then laid the grid pieces on top, with the layer set to Difference.
Ryder Hook did an awesome hand drawn grid/grout, and Bogie cut some of it up into very convenient 4x4 and 1x1 pieces. Here's the link to Bogie's downloads:
Ryder Hook's Grid Template Covers. The link to the original grid is at the bottom of the first post.