Sorry again for the buggy minimal example.
Please try again with the attached version. Instructions as before:

1. Evaluate the elisp code contained in the section "Code to
evaluate", either by executing =(org-babel-load-file
buffer-file-name)=, or by evaluating manually each function using =C-x
C-e=
2. Run the small tests contained in the section "Transclusion tests"
using =(org-babel-execute-buffer)=. This will behave as expected
3. Restore the buffer to its original contents using =C-_=
4. Now, run =(org-babel-exp-non-block-elements (point-min)
(point-max))= and compare with the behaviour in step (2.)