Regarding woodgrain, you can still use the plugin's Real Scale feature when assigning by layer. Try this:
- make two longish boxes, one aligned with the x axis and the other with the y
- drag a woodgrain material onto their layer
- open the plugin's material editor
- if the material editor's texture panel is not open, open it
- hold down CTRL+SHIFT and toggle on the Real Scale button (in the small toolbar below the texture preview, it's the one with an 'm' on it)
- if it was already on, cycle it off, then back on, while holding CTRL+SHIFT - that key combination makes texture changes apply to all textures in the material, so you are just making sure Real Scale is enabled for all textures
- you should see the textures equalize in size in the viewport
- if the size is not in the right ballpark, hold down CTRL+SHIFT again and adjust the texture's Tile X/Y values until it is
- to adjust the orientation, select the first box and go to Object Properties > Maxwell Object Properties
- in the Real Scale Texture Control group, adjust the texture's x/y/z axis orienatation so the grain is suitable this box
- do the same thing for the second box
Now, if you move/scale/rotate these boxes, the plugin will adjust the texture size to maintain the real size you have set - Real Scale means that the texture's Tile & Offset values will be specifying an actual meter-size for the tile, rather than specifying how many repeats as is done when Real Scale is off.
In case it's hard to understand what the heck I'm talking about, there's a tutorial about using Real Scale in the Maxwell for Rhino plugin here:
http://think.maxwellrender.com/maxwell_ ... e-134.html