I think your slow jog may be due to the machine not being refrenced. Once you do a sucessful home, I think that will go away and you will be able to rapid. That may be why you can only jog one axis at the time as well. You can test this by disabeling your home switches in config, ports and pins, inputs and refrencing the machine. That will make the machines current position machine 0.0000. Just rememeber, when testing, slow things down and be ready to stop it should it not act as you expect.
I'm not sure about the simulate button on the diag. screen (mine doesnt have it) but you can emulate the limit switches by setting them to do so and assigning a hot key in config, ports and pins, inputs.
Brett