Sorry. I'm back again! I'd be very grateful indeed for some assistance with clearing up my confusion.
1 - Am I right in assuming that what's called "Contract size" in MT4 is what fxDreema calls "Volume size"?
2 - When a broker says the minimum "Contract size" is 1, I can set a lesser figure, say 0.1 in fxDreema. So, if I set in 0.1 in fxDreema, and run a back test the contracts traded are 1 in size. I assume therefore fxDreema is simply saying, "trade at 0.1 or whatever the minimum contract/volume size set by the broker". Is this correct?
I did do a search in the forum for this, but didn't find anything conclusive. But sorry for what is probably a very silly question! 
Thanks again.