I am sorry but the fixture you are requesting is not compatible with cuety. Each mode of this matrix use subfixture/pixel command (even the 12ch mode with the background color control) and cuety do not manage subfixtures.
IF you want to use a pixel mode like the 147ch one, the best is to patch 49 RGB LED par from the "generic" manufacturer. It will take a lot's of fixture slots but you will be able to control each pixel.
I usually don't do custom file for cuety but I join to this post a file that will allows you to use the 12ch mode. Just patch the 12ch mode i provide to your fixture address and then patch 1 RGB par at address+11 ( this RGB LED par will control the background).
I hope this will help you.
Enjoy
