Update 'plugins/customoregen.md'

plugins/customoregen.md

@@ -23,6 +23,8 @@ In order to run CustomOreGen, a SkyBlock plugin needs to be installed and runnin
 3. Restart your server (Using the /Reload command is not recommended!)
 
 # Creating a Generator
-**IMPORTANT: When making generators, make sure to use Bukkit material (block) names. A list of the Bukkit material names can be found [here](https://hub.spigotmc.org/javadocs/bukkit/org/bukkit/Material.html).**
+**Important notices:** 
+
+When creating generators, make sure to use Bukkit material (block) names. A list of the Bukkit material names can be found [here](https://hub.spigotmc.org/javadocs/bukkit/org/bukkit/Material.html). You must also make sure all of the materials under one generator category have a total chance of 100.0%. For example, in the screenshot below, STONE has a 50.0% of being produced, SANDSTONE has a 40.0% chance of being produced, and IRON_ORE has a 10.0% chance of being produced equaling the 100.0% (50.0% + 40.0% + 10.0% =100.0%)
 
 ![](/media/CustomOreGenConfig.png)