Is the OnSlotChanged callback also able to block the slot change?
it's an "-ed" event, so no. Blocking a change would be quite difficult to implement; it's much easier to do it in the plugin
I can't believe it ;D my pattern password is actualy working

Now that you know how to use them, it would be great if you could document the new classes in the wiki
Note: cLuaWindow actually inherits some of its methods from the generic cWindow class
I've found a bug: If you drop an item from a cLuaWindow, the OnPlayerTossingItem hook doesn't get called.
Does the hook get called if you drop it from a normal window?
That hook only gets called for when the client sends the Q keypress packet.
"Drop" key

For me dropping stuff is "C" ;D
Is there a way to block a player throwing some stuff out of the inventory?
No, not yet.
I could make an interface so that plugins can monitor window click actions, but their interpretation is really twisted and would be difficult to set callbacks for.