I think I am very close, I hope.
I made two cells with multiple letters replaced with their initial letter.
Then I switched the two letters in row with 30a.
That gave me the correct playfair code for the fifth letter in 13d.
But I have four other cells with with multiple letters.
Last of 32a, First of 34d and third of 41a and last of 16a.
Plus the two in the row of 30a.
I have 6. Preamble says 4.
What is my mistake?
Thanks.