-Three multiplier score fields (based on color of course)
-Each multiplier score field doesn't overlap the other (starts multiplier over gracefully)
-limiter to how soon the multiplier kicks in
-limits how high the multiplier goes
-should be pretty easy to modify to your needs
Controls are:
<- left arrow to increase blue points
-> right arrow to increase red points
^ up arrow to increase green points
And if you know me I got to have awesome particles!!!!

Particles are made custom for this, might find a use for them somewhere. And all animation done in synfig. You're free to use anything in this.
[edit]
I don't think I've ever ever had my code scrutinized before so I have no idea how efficient the code is or how good a programmer I am lol, so warnings!