Trying to return the phone back to the original files. Problems with Dark Dialer file/folder setup. I do get calls but there is a blank screen, after a message saying, "com.android.phone has stopped". On my land line where I placed the call to my phone, I get an automatic message saying "The google subscriber is not available....leave message..." I do then get a notification on my S4 Active (SGH-I537) of a voice mail, which I can play.
Renamed the original files to original names after moving dark dialer files. While doing this the phone updated a file called TwDVFSApp. Not sure if that update messed with the phone, But after a restart, my phone is stuck on the small round blue and white AT&T logo on a white background. The phone no longer boots. I did make a backup on my external SD card before I first put the dark dialer files into their respective folders.
Now I just have to google how to press the start, home, and volume buttons and how to recover. Will update later. At least I'm scratching the tip of the iceberg, and starting to learn at least a few android ins and outs.