Working with GUI controls is easy, if you have the right magic string containing the name of the control. This is easy and relatively effortless, but I think we can go even further in making this easy for developers!
When the GUI is exported, it should be relatively simple to walk the control tree and use it to generate a JS module containing constants for the control names and potentially even get accessors for them. The resulting code then can be used by the consuming app, helping to keep it DRY.
Perhaps this exhibits in the editor as an additional export option; in that case the JSON of the GUI could be combined with the JS module