Unfortunately those cheaper Chinesium RCs dont typically have much support at all which is just one reason I typically advise people to buy something from a quality brand. I hate that you didnt have a good experience with it.
Personally I wouldnt want to run a NiMH in it as the performance and run time will be crappy in comparison. That being said, I tried finding a user manual for the ESC thats in that kit and I can't find one. You'll likely have to contact the manufacturer and ask them for instructions. I did find...