I have just updated my Note 4 to lollipop, I had seen that Google have provided a way to access the SD card. I have a file manager called X-plore, this gained full SD card access with a one time only action on my part. I add my plea for F-stop to be able to do this too – as soon as may be!! I saw that something different may be needed for some types of file but X-plore has no problem creating and deleting folders and copy, moving and deleting .jpg files.
I have to say that at the moment X-plore is the only 3rd party app I have found that has SD card access.