MuseScore Songbook App issues

Thankyou for making the upgraded MuseScore Songbook app functional again.
iOs 12.01

There are a number of functions that were useful on the old version that do not work on the new one.

The new versions mixer settings are not stored and have to be reset every time the app is opened.

The mixer does not do what the buttons say they are doing until they are all pressed again and then set with the original settings.

Some times you cannot turn off an instrument by pressing other solo buttons. Sometimes you cannot get the solo button to light even thought the instrument is playing

The mixer does not have settings for all the instruments (The bass)