Let's see how creative/sadistic you can be! 
I'll start:
1) HEAD FOR HEIGHTS.
One celebrity is walking along a high wire 100ft above the ground. Along the wire, suspended above the celebrities head are 5 boxes, each containing two stars. The celebrity must place their head inside the boxes and remove the stars with their mouths. If the celebrity falls off the wire, the trial is over.
Box 1: Stick insects
Box 2: Yabbies
Box 3: Spiders
Box 4: Snakes
Box 5: A monitor lizard.
2) PIT BY PIT.
One celebrity is tied to a platform which is going to be lowered vertically (or possibly upside down
) one at a time into six narrow pits in the ground. Each pit contains a puzzle which the celebrity must work out in order to accumulate as many stars as possible.
PIT 1: Cockroaches
PIT 2: (Water pit) Eels and Spanner crabs
PIT 3: Scorpions and spiders
PIT 4: Snakes
PIT 5: Hellholes (dipping arm into holes for remaining stars.)

I'll start:
1) HEAD FOR HEIGHTS.
One celebrity is walking along a high wire 100ft above the ground. Along the wire, suspended above the celebrities head are 5 boxes, each containing two stars. The celebrity must place their head inside the boxes and remove the stars with their mouths. If the celebrity falls off the wire, the trial is over.
Box 1: Stick insects
Box 2: Yabbies
Box 3: Spiders
Box 4: Snakes
Box 5: A monitor lizard.
2) PIT BY PIT.
One celebrity is tied to a platform which is going to be lowered vertically (or possibly upside down
) one at a time into six narrow pits in the ground. Each pit contains a puzzle which the celebrity must work out in order to accumulate as many stars as possible. PIT 1: Cockroaches
PIT 2: (Water pit) Eels and Spanner crabs
PIT 3: Scorpions and spiders
PIT 4: Snakes
PIT 5: Hellholes (dipping arm into holes for remaining stars.)