Currently you can't use nested property access (the example I ran into for my game was InputController:jump:packed); the only change necessary to support this would be to call node.get_indexed and node.set_indexed instead of the current node.get and node.set inside of property-entry.gd:

I'm not sure if this was a deliberate choice, maybe for performance, but I've made the change in my game and haven't had issues so far.