I really like to know how to create those pbl hightmaps
more than pbl, you should create the PNG heighmap.
<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">class cfg
this is a pbl file, which point Visitor (when importing) to:
1)-->The PNG you created with Wilbur
2)-->the size of the square, according to the terrain cell size (meters) of your island in Visitor
3)-->the minimal height and the maximum height which are the values of your PNG to be checked in Wilbur.
So, when you have finished creating the PNG in Wilbur, you check the max and min height, and insert it in the pbl file.
I'll suggest you to download Opteryx Tutorial, it's really usefull to start editing!