To recreate:

1. 
   

   Add a UI-only model to a page
   
   I did add labels to all of my UI-only fields

   
   


2. 
   

   Add a form tied to this model and select the fields in the model.

   
   


3. 
   

   Get error message (and form not added to page):

   
   


4. 
   

   There was a problem initializing a component of type skuidbuilder__builderComponent: Cannot read properties of undefined (reading ‘getLabel’)

   
   

Here is the error message on my page:

Here is the model definition:

Step 1 of adding the form:

Step 2 of adding the form:

I can add a basic model form, but not a UI-only model form.