I don't miss anything, i was asking about release parameter (if any, never use this bomb).
But it's seems to be a bug.
Whatever the release altitude (2000, 3000, 5000, ..) the cansiter opens immediately and bomblets are released.
In my post, I specified, "they don't seem to work properly. " so the minimum a person should do before replying would be to check if the mk-20s work properly and the method used (CCRP, CCIP, Dive angle,speed, and so on).
Then perhaps someone can confirm it's a bug or there is a special procedure to use them ?