Changing files in anbox-data
I'm using a physical keyboard on my Nexus 5. Unfortunately in anbox the standard keymap is English whereas my keyboard has a German layout.
Now I found , that anbox can be forced to use an alternative layout if you exchange the .kcm file  in the appropriate directory. (In my case: ...anbox-data/rootfs/system/usr/keychars/).
Great, if I could only do file operations in this directory. It seems like this portion of anbox is an unchangeable mounted image. Thus my quest ends there.
Anyone got an idea how to overcome this limitation?
I found out, how to do it. I will start a new topic for that.