When I installed Ermine first, I had a problem with the library.
After installing Ermine, I moved library to SD and behaviour was not very good, so I did factory reset, without a clear picture of what I would see in my EE after that.

After factory reset, library was again in the internal storage, and Ermine was still there, and the whole thing was working much better.
I haven't tried moving library to SD again, for the time being, until Ermine has a better, more stable development, or until I read more favorable posts from fellow members who have tried this post-Ermine library-move in a successful way.

But all in all, factory reset rearranged things and set apps in a proper operating mood. Good luck with it if you try it. Please remember your data and most of your apps will be erased if you choose this option and you will need to re-register Edge, reinstall some of the applications, and reconfigure mail accounts...

All the best,

Paula