The problems are super hard to diagnose, which is yet another problem.
In Unity when I load a resource chain (i.e. resource dictionaries importing others in a chain to avoid loading resources multiple times), whenever there's a problem in one of the dictionary files,
I'm basically getting

"NoesisException: Assets/NoesisGUI/HelloWorld/MainWindow.xaml(1): Document contains no elements."

from Unity, which tells me absolutely nothing. But under some circumstances I cannot really reproduce it tells me that it cannot parse the string.

To be honest, the fact alone that errors in the creation of resource dictionaries throw such useless errors is already a major deterrent from using Noesis.
We need to be able to understand what Noesis is complaining about. Simply saying a file has no elements, which is clearly not the case, is not helpful at all.