REP-03100: A matrix must include at least 1 Down and 1 Across repeating frame.
Cause: An attempt was made to create a matrix (selecting Arrange, then Create Matrix) without the proper objects selected in the Paper Layout editor. A matrix layout requires that at least one group have a repeat direction of Down and one have a repeat direction of Across.
Action: Select two repeating frames--one Down, one Across--that overlap, then select Create Matrix from the Arrange Menu.
Level: 1
Impact: Other