Crashing and other anomalies in MuseScore 4.

I should say first off, I do not nor ever will use Windows or Mac OS. I use Linux, Ubuntu and Linux Mint on i5, on 16gig machines. Of course, there is no native installation of MuseScore 4 and one uses an app image. This post applies to previous scores downloaded and used to test the program and Muse Sounds. 4 not only incorrectly imports the scores but also changes things like dynamic lines. Plus, when played back, the dynamics are totally strange, with the volume increasing or decreasing with no markings. An abrupt change in dynamic produces a playback that sounds more like a digital glitch rather than a purposeful sudden increase or decrease. I have even had the program crash a few times until I changed the new sounds to MS Basic. Although the new sounds seem quite promising, they are too mercurial and the program too resource-intensive to be useful on a Linux machine. At this time, I am forced to continue to use 3.6.2. One other annoyance is that when I select a point at which to start playing, the program moves to the beginning. Perhaps things will be different once a program is available through the Ubuntu software repository.