When moving the cursor over a curve in a report, the value and the name of the datapoint are displayed in a box. For curves that span a longer range, it is very hard to guess what the corresponding abscissa is. Couldn't it simply be added to the data box?

Have you tried setting "Show data values" in the report Customize dialog?

I found "Draw values on Chart" in the "Chart" tab of the "Configure" menu, but that is not it. Am I looking in the wrong place?