Nope. No screwing or unscrewing involved. First let me familiarize you with the copper colored coil. This coil is wound with a wire thinner than human hair, much thinner. Touch this in any way will cause the wire to sever and the watch is DOA. Why do I point this out? Because 20% of the amateurs that attempt to change their own battery manage to cause their tool to slip and touch the coil. Now notice the small hole on the end of a spring bar near the "S" on the cell. With a pointed tool slowly bend the bar toward the coil and the cell will most likely pop up. Insert a cell and move the bar over the top of the new cell. The screw to the left of the "m" is purposely spaced so the bar can move so do not attempt to tighten it.
Test the old battery to make sure it is the problem. The assumption the watch doesn't work because the cell is dead is not correct. The watch may not work for many reasons and indeed may have multiple problems.
Found some time (about 10 minutes is all it took) to replace the battery, and it worked like a charm.
I didn't have a thin enough tool (probe?) to fit in the eye of the spring bar, so instead I just used what I had ( a broad, flat watch band post remover) and gently pushed the spring bar back until the battery popped up, made sure I was putting the battery on top of the contacts that are under the battery to the right, pushed down gently on the battery, let go of the spring bar, and it was done.
Now it's ready to sell. Thanks again dacattoo!