I didn't know where to post this, but I figured it would probably be seen here, so here it goes.
As for now, the property "raycastLayerMask" of tk2dUIManager is public and is only assigned to sorted cameras' raycastLayerMask at tk2dUIManager's start. This caused a problem when I had to dynamically change the layer mask in-game.
Wouldn't it be a good idea to turn that public property into a private one with a Getter/Setter, that updates every sorted camera's raycastLayerMask when set to a different value?
That would greatly simplify tk2dUIItem disabling. This is a simple idea I got, and I thought that sharing this with the dev team, would maybe give you some hint on further updates.
Regards.