hi Piers,
personally it looks like you have gone to far to soon, you have made to many adjustments on this map and lost your way a bit. i would suggest saving the rom, but go back to the original map you started with and see if the knock goes away in the areas you are looking at.
then start again but make smaller and more considered changes to the map.
keep in mind that after making adjustments on the cells you need to make adjustment s to you need to change all the cells around them to smooth the map out so the ecu make smooth changes to the timing and AFR when it adjusts itself when knock come in.
have you watched all the videos in the this thread it will give you a very good idea about what to do and what not to do when tuning a map.
https://www.clubvr4.com/forum/showth...basic+ecuflash
i had to watch them 5 or 6 times each to get a good idea on how to tune a map, it is not easy to get your head round and get things right, if it was everybody would be doing it.