With stills, I had write errors when shooting panorama, CH, CL, long exposure etc and using a slower card. Had reported to Fuji here and as expected the issue was never heard of by them in spite of sending them links to the issues. But they were very helpful in loaning a camera, a faster card and they took my card to try on their camera. It was concluded by Fuji that the card was slow. And the truth is, I switched to a faster card and haven't seen the issue after that.
Also, I never delete the images in camera or computer. I switch to read only when reading images from a computer or copying.