Composer Memories A, B and C are used to store styles which you have either created from scratch, or modified built-in styles, or loaded using the 'Composer' option in SD Card or Floppy Disk load options. They are not necessarily linked to the Panel Memories A,B and C. However, if you have the Panel Memory Mode set to operate in Expand Mode and in the Expand Mode Filter, the 'Filter Type'/'Rhythm Selection' is set to 'ON', then you can link changes made in Panel Memory to change the Composer Memory Banks A, B and C and/or Variations 1-4. To do this, you just need to select the desired Bank/Variation of the Composer and along with other Panel settings, save in a selected Panel Memory. If the 'Rhythm Selection' parameter is set to OFF, then changing Panel Memories will have no effect on the Composer settings.
For example : If I use a Composer style which has say 8 Variations ie 4 in Composer Memory A and a further 4 in Composer Memory B, then along with other panel settings (sounds, effects, Technichord etc.) I would Select Composer Bank A, Variation 1 and save in Panel Memory Bank A, Location 1. Then another panel set-up and Composer Bank A Variation 2, in Panel Memory Bank A, Location 2, and so on through to Composer Bank B Variation 4, stored in Panel Memory Bank A Location 8.
Using this method, I just play the song and progress through the Panel Memories 1-8 as the song progresses, which makes it a simple process for changing set-ups within a song.