I don’t know about the first item listed, but I do know about the second item. When you move a block to create a diamond, if that block you moved is frozen, it will not create the diamond, it will just un-freeze the block like normal. However, if the block you move is not frozen, it will create a diamond. Same with creating the dragon heads.
However, what I don’t know is, if the diamond is created during a cascade, I haven’t figured out if there’s a pattern to which tile the diamond is created on. But, if the diamond would be created on a tile that is frozen, then the same thing happens… The tile is unfrozen, but no diamond is created.
It all depends on where th RNG allocated the “seed” having been for a cascade diamond. If it allocated it to a frozen block it’s the same as if U matched (swiped,/ swapped) in a frozen block. The block is unfrozen and thus cannot be morphed