As BouncyLion said you really should download GIMP - it's a fairly easy program to use and it makes map and preset work so much easier to do - c:
If you're new at making maps check out these links (these tutorials use GIMP and can make it easier for you to get familiar with that program):
\\Terrain Height Maps// (http://www.feral-heart.com/index.php?option=com_jfusion&Itemid=2&jfile=index.php&topic=10098.0)
\\Making Maps// (http://www.feral-heart.com/index.php?option=com_jfusion&Itemid=2&jfile=index.php&topic=17452.0)
Good luck! // Shallow