Hi @jdugh,
Thank you for bringing this issue to the community and providing a clear sample for discussion. I tested it at my end and wanted to let you know that i did not see the error message that you have been seeing.
Furthermore, i just wanted to let you know that if you click the first + sign it will make a repeat to Level 3 only. Similarly, if you click the second + sign it will make a repeat to Level 2& 3. Similarly, if you click the third + sign it will make a repeat to Level 1, 2& 3.
For details, pleas see the image as shared below:
If you look at the shaded part closely, you should be able to see the repeat groups that has been shaded distinctly. Maybe this should help you understand the nexus of the nested repeat more clearly.
Have a great day!
