Do what He says above.
I found the new offset in the gcode (and used with GPX etc) works great. The "old" way with 1.1.2 works also but does not keep the object in the middle of the virtual build plate during simulation so the "new" way seems better if not only by way of looks during sim.
Though it may not work if you pull the gcode and render the x3g with repg as I did with v1.1.2 for a time . . GPX seems to fix some of the codes?
Also I am not sure what you meant by flipping x or y? all I needed to do was move the origin.
Sure I will upload another after I insure it works and then export it!
Really there is not much to change from the default rep2 one they have . . Just a fix for the HBP and wipe instructions for the 2x (the x is too far) boost the temp and minor things like that.