Are these clips generally shorter clips with long names? I’ve noticed as I edit that when the little “x” shows up, it is typically on a clip that is short and has a long name, but if I zoom in on the timeline, the waveform shows up, once it has more room. Not sure why this is. Also, I’ve never seen the first problem you had, with the black and white in the Viewer window, not sure what that could be.