Set it to .6 amps. The volts will take care of themselves on a NiCd. Don't use the NiCd that came with the plane unless you are certain it's less than 3 years old. I highly doubt that's the case, as 600 mah NiCds haven't been the standard flight pack battery for quite a while.
I'm going to strongly suggest working with an instructor with your trainer. The simulator can teach you a lot, but it can't teach your proper setup or how to deal with a badly out of trim plane. It also can't take over for you when you realize you are in over your head on those first few flights or recognize that you've lost orientation and so are confused about which way the plane is pointed. There is a good reason the tried and true hasn't changed much in the past few decades.