Hi again, I took a look at the tutorial site you mentioned and I think this may be an even better solution. Thanks for the link though as its what gave me the idea.
1. Create a new image 100X100 pixels with a transparent background.
2. Select the Rectangle tool
3. Set line width to 1 or 2, uncheck vector, and use either rectangle or square as the shape. Anti-aliasing will make no difference because of the line type so un-check it.
4 Using only foreground coloring (disable the background pallete) Draw your square from corner to corner. It should look like this.

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Now save the image to your "Program files/Jasc Software inc/Paintshop Pro 9/Patterns" folder as "MyGrid.psp".
To try out your new grid, use the flood fill tool and select pattern then click on the forground color panel to open the "Material Properties" Dialog. Click on the Pattern tab, then select your new grid pattern from the pulldown menu next to Current Pattern.
This will give you a permanent and scaleable Grid you can access easily any time you want to use it. Thanks to you and your link you and I can now have an easy to use grid that is easy to access and versatile.
Hope that works for you, but if you have trouble let me know and I will be happy to help in any way I can.
PS. I have attached the Grid image in zip format so you can simply unzip it to its proper location, that will save you quite a bit of hassle
Regards