How to change text to NBT in GUI after new update

Hello, i wanted to ask how to set a text inside a GUI to be a NBT tag (or anything else) after the update 

The update kinda broke the previous way of doing it, which was to name your text label to be : <BNBT :number:energy> for example 
Now this doesnt work, and i can't easily access or show the different value my blocks have inside their GUI anymore, is there a new way of doing it ? Or a way to re-implement the old way of doing it ? i noticed when making a text field that you "could" change it to be somethign else than "fixed", but nothing elses shows. So no setting the text to be a NBT tag there apparently...