Please add the optiont to prevent larger than normal stacks from being placed into chests. If a player can drop a larger than normal stack and if another player that doesn't have the permissions to form a larger than normal stack can pick up said stack and it remains a larger stack then please add the option to prevent a player from dropping a larger than normal item as well.

Preventing chest interaction and dropping items and then tying those abilities to permission nodes has already been implemented by the plugin "Grounder" and it works quite well. Maybe you could collaborate or borrow code if it is open?

I think a better solution would be to have anyone with lesser amounts only pickup the amount they can at a time. So if there was a stack of 100 in a chest and a player comes along that can only have stacks of 50, they would then get a stack of 50 on the first click and another stack of 50 on the second click.

I agree with that. If you can add this that would be great!

The test version here has that implemented now: https://github.com/haveric/StackableItems/tree/master/versions/test

Please try it out and let me know if there are any issues or problems with it.

Just installed it and got this to the console:

6.06 11:38:04 [Server] INFO ... 7 more
06.06 11:38:04 [Server] INFO at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:190)
06.06 11:38:04 [Server] INFO at java.util.jar.JarFile.(Unknown Source)
06.06 11:38:04 [Server] INFO at java.util.jar.JarFile.(Unknown Source)
06.06 11:38:04 [Server] INFO at java.util.zip.ZipFile.(Unknown Source)
06.06 11:38:04 [Server] INFO at java.util.zip.ZipFile.(Unknown Source)
06.06 11:38:04 [Server] INFO at java.util.zip.ZipFile.open(Native Method)
06.06 11:38:04 [Server] INFO Caused by: java.util.zip.ZipException: error in opening zip file
06.06 11:38:04 [Server] INFO at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
06.06 11:38:04 [Server] INFO at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:432)
06.06 11:38:04 [Server] INFO at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:166)
06.06 11:38:04 [Server] INFO at net.minecraft.server.ServerConfigurationManager.(ServerConfigurationManager.java:53)
06.06 11:38:04 [Server] INFO at org.bukkit.craftbukkit.CraftServer.(CraftServer.java:189)
06.06 11:38:04 [Server] INFO at org.bukkit.craftbukkit.CraftServer.loadPlugins(CraftServer.java:213)
06.06 11:38:04 [Server] INFO at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:132)
06.06 11:38:04 [Server] INFO at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:202)
06.06 11:38:04 [Server] INFO org.bukkit.plugin.InvalidDescriptionException: Invalid plugin.yml
06.06 11:38:04 [Server] SEVERE Could not load 'plugins/StackableItems.jar' in folder 'plugins'

It didn't create the 'stackableitems' folder either.

That sounds like the file got corrupted. Try redownloading it.