This app has really lost a lot of functionality, making complex apps is almost impossible due to the fact that you cant do things as basic as setting the position of an object.
Ex. You cant put a block here which makes objects almost completely useless
You cant change the color of things in the list viewer
There is no to number
I think that the api needs a complete overhaul of features
The property here would be for the objects you are working with. Depending on whether you created it yourself or if you are working with an API then the properties names will already be known to you in advance.