Order - This is the order in which the Left Matrix Configurations are applied, when there are multiple Left Matrix Configurations with the same Parent.
Matrix Config Name - A name that you can use for keeping the Matrix Configuration details straight. This is not shown anywhere but here in the configuration interface.
Parent - Select another Left Matrix Config to be this one's parent. This is important when you need to define multiple Left Matrix Configuration records in cases like having Categories, and Sub Categories along the left side. Define Categories as Order 1, with no parent, and Sub Categories as Order 1, with Categories as the Parent. This will affect the starting context for the Header and Body Items; so if you make a change to this field, save the row to see that context change.
Header Items - A query that allows you to choose the records to show down the left.
Header Fields - Choose the field(s) that will represent each of these records down the left.
Label - A label to use for the Left Matrix records.
Header Color - A Color that will be applied to this level of the Left Matrix when it's rendered. Accepted values: Color Names, or Hex Colors.
Body Items - A query that allows you to choose the records to show in the body, for this Left Matrix Config. This query starts where the Header Item's query leaves off.
Body Fields - Choose the field(s) that will represent each of these records in the body.