Using ray of frost to free water is something that in dnd would in most cases be left up to dm interpretation in heavier rp games most dms would let something like that apply just most players for games do not think outside the box. The idea behind the game was to make it similar to dnd where thinking outside the box is encouraged. Thus several mechanics. Not just ray of frost where this could be used.
However, I'm sure most DM's would object to "The spell freezes the gallons of blood which had spilled from the target after it took that 1 point of slashing damage".
