Opening Dorico 4 file

Hi,
I would like to ask for your help.

Here is a file with many flows, created in Dorico 4.1. Unfortunately, I’m not able to work on it in the current Dorico 6.1. Dorico opens the file, but there is no musical content — only the flow structure is visible.

If anyone has an earlier version of Dorico, could you please let me know whether this issue occurs there as well?

Thank you in advance.

Rhythmic Exercises.dorico (1.2 MB)

If I open this in v5 or v6, there are no flows in the project.

If I open this in Dorico 4, there are still no Flows in the project – just 36 Woodblock Players and Layouts. But no music.

I’m sorry, I described it the wrong way. Yes, there are many players, but no flows. Interestingly, when I add a new flow, it is named “Flow 2”. I remember quite well that I created these exercises a long time ago and thought I would come back now to finish them, but there is no information at all. Thank you for taking the time to open the file.

Search for any Dorico backups of that file and open them all to check if there is anything different there.