HideZeroValues Flag is set to False as default value.
If you change it to True is not possible to set it back to False.
I found this bug in frClass unit
procedure TfrCustomMemoView.SetHideZeroValues(AValue: Boolean);
begin
if WordBreak<>AValue then
ModifyFlag(flHideZeros, AValue);
end;
To correct the bug you need to change it in
procedure TfrCustomMemoView.SetHideZeroValues(AValue: Boolean);
begin
if HideZeroValues<>AValue then
ModifyFlag(flHideZeros, AValue);
end;
Regards
Luca