After I changed a battery on R0614ZM TERNER watch, the display went berzerck and then blank altogether. Any ideas at all?

Some watches have a "reset" button or combination of buttons that must be pushed to clear all the electronic registries on the watch's little computer after you replace the battery. You might try taking off the watch back and seeing if your watch has this requirement. Even then, it's not always a perfect solution. Last week, I replaced the battery in a watch that had been dead for some time. The watch appeared to come alive again when I put the new battery in, but when I pushed the reset pin (on this movement, it was on the watch movement itself, next to the battery), the entire watch went dead. Nothing I did would wake it up. I removed the battery, waited 30 seconds, then re-inserted the battery. Problem solved; the watch powered up, and I was able to set the time and access all functions again.
On some digital watches from the 1980s, after replacing the batteries, you were supposed to push and hold all the external buttons for a few seconds to reset the watch. I don't think manufacturers still make watches that respond to this, but it is easier to try than taking off the back and re-installing the battery.