Help please on DM542T Stepper Drivers

[AndyUK]

I think I have to select the slightly lower Amp setting on the currant table so 2.84A for the 3A motor but I want to check this is right?

Looks sensible to me.

the Pulse/rev table I just cant figure out in my head what to set it as?

This is just setting the microstepping factor - it doesn't really matter which you select, they'll all fundamentally work, but the higher the setting the smoother your motors will be, and they'll be able to position more accurately - but this comes at the cost of reduced torque. Usually 1/8th is a good starting point (1600 pulse/rev).