Also, I managed to fix the problem by inserting
img.alignright {float:right; margin:0 0 1em 1em}
img.alignleft {float:left; margin:0 1em 1em 0}
img.aligncenter {display: block; margin-left: auto; margin-right: auto}
.alignright {float:right; }
.alignleft {float:left; }
.aligncenter {display: block; margin-left: auto; margin-right: auto}
At the end of the style.css at the suggestion of another support thread. I’d been trying to modify the existing image tags, which hadn’t been working.