Thanks, I now have 5,10 of 16 ac, but brain is a little dead as to working out the second part. Definitely not on this wonderful compiler's wavelength today!
There's a good hint from SDKL on the other thread.
Have you worked out which grid goes with which composer? The clue is 10ac, which gives a name, which has to be in A as the composer's name doesn't appear in B.