Background:
I have a TIB_Cursor which I am passing to one of my classes as a
TIB_Dataset.
AutoFetchAll = True
AutoFetchFirst = True
ReadOnly = True
RequestLive = False

I set the SQL dynamically then call
FDataset.SQL.SaveToFile('datasetSQL.SQL'); // For debug
FDataset.Prepare;
FDataset.First;

I get no data back.
EOF = True
If I try to access the field values I get an exception.

I have tried casting back to a TIB_Cursor; but that made no difference.

In the IDE, if I Edit the TIB_Cursor and paste the contents of the
saved file ('datasetSQL.SQL') into the SQL of the Cursor tab I get the
correct data that I expect at run time.

What am I missing?

Many thanks,
Clive.