Error while compiling: StackSizeController.cs(650,66): error CS1503: Argument `#1' cannot convert `uint' expression to type `ItemContainerId'
(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 35)

I am having the same problem.

Thanks @larinem, that worked for me.

ExplosiveShart

@larinem That's in the .cs file right? I opened it in notepad++ and it only goes to line 623.

Yeah the latest update only goes to 623 in my editor as well.
I got the previous update and downloaded, then changed the line as instructed and it seems to be working again on my server.
v.odd

https://umod.org/plugins/stack-size-controller#updates

The latest version of the plugin still does not work on my servers. I have to use the second last with the fix of 

larinem

Try to replace line 641 with this:
        object CanMoveItem( Item item, PlayerInventory playerLoot, ItemContainerId targetContainer, int targetSlot, int amount )

to make it work :D Very strange!