Trouble with Creating custom regions

[rulingsword 0]

I am trying to create a region that I chopped off of one of the custom maps here.  The original is fairly large at 4097 by 3073 with a config.bmp of 64 by 48.  I only want a smaller portion so I trimmed the image accordingly using microsoft paint.  The image is now 3073 by 1537.  I then created another config.bmp that is 48 by 24.  I followed the omnibus guide as to how to create the region and was able to create a directory and at least a rendering of a flat region corresponding to the new config.  I then pressed CTRL-ALT-SHIFT-R and was able to get the browsing menu and select the new file.  Once I select it, the window closes and nothing happens.  Absolutely no effect occurs.  

When I use the original file and config, however, I am able to get the creating new city screen but this region is way too large and I normally run the game at low settings just to tolerate it at large populations.  I went ahead and interrupted the rendering of the larger region as I would much rather have the smaller cut.

Does anyone know what I may be doing wrong in editing the original file?

[Hamish 1,369]

You probably didn't save the image as a greyscale. Try that. Because if the .jpg isn't a greyscale, then it wont render the region.