Rob, I tried to PM this to you, but apparently I do not permissions to do so. I am trying to follow your tutorial on creating a world, but no matter what I have tried I can not seem to duplicate the following step:
Now Invert the selection (Select->Invert), create a new black layer called “Land Mask” and fill the selection with white. Now save the selection to a Channel (Select->Save to Channel) and rename the channel to “Land Mask”. This will be used a fit bit later.
When I do this, I get a sheet of white with no features on it. I am missing something, but not sure what. Any suggestions?