PlutoRowGroupByColumnDelegate - how to show expanded by default

[rrF430]

When using PlutoRowGroupByColumnDelegate as per the example, default setting is that all the rows are grouped. I could not find an easy way to set the default in expanded state.

Another nice to have feature if there is a setting where there can be a mix of expanded and grouped rows "onLoaded" (but not as important for me as the first request above)

Buried somewhere was flags like setExpanded but i don't how to access these

Any assistance is greatly appreciated
Thanks
RR