This window allows you to save the texture UV mesh to an image that can then be used to paint the texture. To access this window, click 
a node.
Filename
The directory path and name of the image to save.
Resolution
The resolution of the image.
UV Layer
The uv attribute to use in generating the mesh (uv, uv2, uv3, etc).
Remove interior of connected regions
The default behavior is to draw the edges of all polygons. Turning on this option will remove the interior edges, leaving only the outlines.
Ignore visibility
Turning on this option overrides the default behavior to respect the visibility of polygons as set by the visibility SOP.