On a matrix form, the top matrix configuration settings allow you to pick the records that will show across the top of the matrix, and define one side of the intersection of records to show in the body area.
Settings
Order - This is the order in which the Top Matrix Configurations are applied, when there are multiple Top 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 Top Matrix Config to be this one's parent. This is important when you need to define multiple Top Matrix Configuration records in cases like having Categories, and Sub Categories along the top. 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 across the top.
Header Fields - Choose the field(s) that will represent each of these records across the top.
Label - A label to use for the Top Matrix records.
Header Color - A Color that will be applied to this level of the Top 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 Top 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.
