I'm also having trouble changing the chart title using VBA. I've tried
recording a macro for it, but then I got an error when I ran the
recorded macro! One variation of the code I am trying to use is

With Sheet6.ChartObjects(chart)
.ChartTitle.Name = Cells(r1, 1).Value
End With

chart is a string variable with the name of the chart, in this case
chrt.Indicator1.

Thanks for your insight!