Tweaking the recording settings from .NET has caused the breakdowns to move to a different transaction type or stopped reporting breakdowns.
Tweaking the recording settings either turned off the breakdowns, or they shifted to being reported to another transaction or transaction type (this often happens when EU finally gets configured correctly). If you had a very large time range,you would still see breakdowns in the RTB tab, but when they drilled down there would not be anything in the current time slice. Also the data retention for those breakdowns is limited, so if you were looking in the past, it could be removed.