WorldGenSeed

The WorldGenSeed is exactly as it sounds. This value will become the seed for the randomly generated map. This will only change anything if your GameWorld property is set to RWG. An example is shown below:

<property name="WorldGenSeed"  value="IceCap"/>

WorldGenSize

Similar to "WorldGenSeed" the WorldGenSize will change the size of your randomly generated map. This value works with WorldGenSeed to create the base seed of the server. This control your height and width. This value has to be a number between 2048 and 16384. Keep in mind the larger the server is, the harder it will be on the machine. While in-game performance is not likely to suffer, login times ans erver reboots will take much longer. An example is hown below:

<property name="WorldGenSize"  value="3455"/>