version 1/080522 by S John Ross
This isn't an elaborate extension, but it's pretty spiffy as far as it goes. It's worth bearing in mind, however, how far it DOESN'T go.
Dice-Lock preserves random results by rebooting the game's RNG with a seed stored and manipulated as a number variable (the "DiceLock"). This preserves selected results against simple UNDO (or SAVE/RESTORE) workarounds but it's far from bulletproof, and errs on the side of simplicity and trust. Like anything I do, it's for players like me, and in this case that means "honest, but sometimes led astray by easy temptation." This game eliminates an easy temptation, but in truth that's ALL it does. That said, it should be sufficient for a good many games, and it does have the advantage of being very tiny and easy to modify(it requires no understanding of I6, and given who wrote it, not much understanding of I7, either).