First, the TitleFormat property must NOT be set to "THIS IS MY %SUM:BITS%, but only to "THIS IS MY ", since there are two properties, StatFieldName and StatFunction, that serve this purpose. You need to do it only on the SummaryRow.TextFormat because these properties are not on the SummaryRow.
Second, the TitlePosition property sets where the "THIS IS MY " title is displayed. The TitleFormat is always displayed in the SummaryCell next to the one running the statistical function, for the function uses the whole cell to display its result. If you use the first SummaryCell, you need to set the TitlePosition to right, else the title will not be displayed. If you have set the TextFormat on the SummaryRow, then you cannot use the first or the second SummaryCell (or any cell that the SummaryRow writes to for that matter), for the statistical function result will be displayed over the TextFormat of the SummaryRow. In the second cell, if you set the the TitlePosition to right, then it can work if the SummaryRow.TextFormat is limited to the first cell.
This is a long description, a bit hard to follow, but once you understand how it functions, then you will have no problem using this functionality.
André
Software Developer
Xceed Software Inc.