There is problem with rendering grouped multilevel columns if data model contains hidden column as first column.
Example here:
https://plnkr.co/edit/RjGTAVkZDXDMj11s (Note: Preview on start has error, but if you try to change on example document something than example with be previewed without an error)
So, the problem is columns AAA and BBB built separately, not under ShipCountry and Customer Name columns like I expect based on Column Model description. Additionally I find out that if this Hidden field move after grouped columns everything works fine.
But still important to know is it possible render correct with leading hidden column?
Thanks in advance!