Progress bar and free navigation

Hi everybody,

I'am developing an elearning course including 25 screens splitted in 4 sequences.

My problem:

- I absolutely need a progress bar to show the learner his progression in the whole module. It should appear on each screen

- The navigation is free, which means I can't use a simple way to do it.

For instance, if the learner visits 2 screens in sequence 1, then jumps to sequence 2 and see 2 screens and then goes to the sequence 3, for instance, I need the progress bar to displays the state corresponding to 5 screens visited

With the only way I know, if I visit 5 screens and then use the previous button, or I jump directly to the last screen, the progress bar does not displays the real number of screen I visited.

I attach an example of the method I used, if someone can correct it, it would be so great

thanks in advance