I can confirm this problem as well.
Having trying out the iOS-platform for a while I went back to the Android platform. So I logged into my google account on a new S10 plus, it restored my apps. Poweramp included.
I copied over my folder with music and noticed quite quickly the same problems that some other person mentioned. The songs skips and I get something like "could not be played" a lot, can not remember the exakt phrase.
The same thing others describe is also hitting me, the thing where I can not select folders but only choose internal storage.
I am not comfortable i