here you see the alterations. The last one (rotating the upper back part ) is only done, when the back crotch is too long and the back fabric needs to be go up. Setting the waist band down is not the right thing.
lg
posaune
Thanks posaune for the diagram, which made the alteration very clear.
Here's what I did. No left/right or upper back part changes yet.
This is the back fork with an extension pieced on. The blue chalk line is the new cutting line, showing the fork extension and a little scooped out of the back.

The front fork:

And here is how they fit. She says the pressure at bottom of fly has been relieved:




The only thing she doesn't like now is they ride up when she sits down:

Does this mean the thigh is still too tight, or is there another issue?