instrument names versus part names; custom templates

I am building a template in Musescore 4 for the combination of instruments I frequently use (The Dutch version of a windband: saxophones, flugelhorns, horns, trumpets, trombones, euphonium, tuba and percussion). I begin by adding all the instruments I want and change the names in the Instruments panel to what I want them to look like.
When I go over the the parts panel I see that the names I entered in the instruments panel don't get copied to the parts panel. This means that I have to change the default names in two places. In Musescore 3.6 this was not necessary.
After I have changed the part names to what I want (like in the instruments panel) and I close this file and reopen it again: the changes I made in the parts panel are lost.
So my conclusion: the parts panel is at this moment not functioning as you would expect.
One other problem is that I can not open the template I just created through choosing a custom template. When I hit the link to the custom templates, Musescore crashes. I now open the template as a normal file and start from there.