Hourglass. It's terribly bug and it'll freeze at some point unless you use Windows XP (or a VM with it). MoF+ games can't normally save replays, you need some trick Kopiapoa does (he's who makes most of the Extra scorerun TASes).
Otherwise there's Cheat Engine, but it just gives ability to slowdown, not savestates. You can get some savestates by using it inside a VM, but it's really unpleasant since it takes like 30 seconds to restore a state.
Btw if you're not aware you can see the TAS scoreboard
here.