Storm of Saruman

If the spell has damage divided as it was put onto the stack, the division can't be changed, although the targets receiving that damage still can. The same is true of spells that distribute counters.

If the spell that's copied is modal (that is, it says "Choose one —" or the like), the copy will have the same mode or modes. You can't choose different ones.

If a permanent spell is copied, it's put onto the battlefield as a token as the spell resolves rather than putting the copy of the spell onto the battlefield. The rules that apply to a permanent spell becoming a permanent apply to a copy of a spell becoming a token.

You can't choose to pay any additional costs for a copied spell. However, effects based on any additional costs that were paid for the original spell are copied as though those same costs were paid for the copy too.

Any choices made when the spell resolves won't have been made yet when it's copied. Any such choices will be made separately when the copy resolves.

The token that a resolving copy of a permanent spell becomes isn't said to have been "created" and won't interact with abilities that care about tokens being created, such as that of Rosie Cotton of South Lane.