I've had some offline time due to travel, or I'd have responded sooner.
For some reason I was confused and thought that the Simple Metal was the model with the Rev G board that required cloud-based operation.
So yes, you have done the right thing in reversing the Y motor plug. There's a "sticky" post in the forum that shows you where 0, 0, 0 is on all Printrbots
viewtopic.php?f=16&t=3484. However, some Printrbots "home" Y to Max instead of 0. So beware. Take a look at the reported value of Y when the printer is "home" to see if Y is zero or Max.
I really use Repetier all the time, even on my new Prusa MK3S printer. I just love the insight it gives into the printer's actual condition as well as controls that you can apply even while a print is running (speed it up, slow it down, tweak the flow rate, adjust temperatures, adjust fan speed...). I think that Printrbot abandoned Repetier because it's no longer strictly freeware; they ask for an optional donation when you download the latest copy. But as Mooselake said, once you have Repetier Host on your computer, it is totally independent of the Internet.