To create a map, open the Map Library and click on Create. You will be given an option to create a map in 3 ways:
If you click on From File, d20pro will remember the last place you imported from and you will be given a brief window that lets you browse to the location of your graphic. Find the image you wish to import and double-click it. If you click on From Clipboard, you import the image directly from memory.
Next, you will see a window with your map and a grid overlay. Depending on where you got your map from, it may have grid lines on it already. If this is the case, the map's grid and the overlay grid will probably not match up, but that's OK for now.
d20pro\judge\campaign\____\res\FLR folder, and then a subfolder with your module name - so give the module name some consideration.
At the bottom of the window, you will see the current map dimensions in 5' squares, as well as a slider to adjust the grid size. You can also adjust the grid opacity, color, and canvas colors. Play with the grid size slider and move your map around by clicking & dragging. Eventually, you should be able to line up the grid to the dimensions that work for you. When you are happy with the results, click the green check icon and your map graphic will be imported and a new map created for you.
When you click on this option, you get a window that allows you to specify the map name, module, and dimensions (in squares). Once you accept, you have a blank map that you can work on. You should then open the Tools window and see the Map Tools page for more information on the tools available to you.