The scientific name of the flinders range scorpion is Urodacus elongatus
I found these caresheets on them: http://www.venomlist.com/forums/index.php?showtopic=18092
To answer your questions, here is what I learned off the web:
1) If your area ranges between 20C to 30C which is 68 to 86 degrees Fahrenheit, you do not need a heat source. If you wish to get activity out of your scorpion, get a heat source (infrared heat bulb) and keep the temperature in the 80's.
2) The authors of these caresheets suggests a 50/50 mix of coco-fiber and soil.
3) The humidity is suggested to be 60-70%
By the way, they don't appear to do well in groups, so keep that in mind.