Hey there, thanks for the feedback, the thing is, there is a infinite amount of work to be done in the app, so i really depend of users like you to tell me what is the places that really need fixes so i can put those problems on top of my TODO list.
I always knew that the file explorer was problematic, but now i can put this to be fixed sooner since users like you are having so much trouble with it.
The app running in the background is something i didn't noticed, will try to fix it in the next version as well