For anyone who has the software with their xpap,   do you find leakage during use more or less a flat line? Regardless of mask or sleep position, my leakage graph is all over the place.....

It usually isn't a flat line.  On an Auto titrating machine it will go up as the pressure goes up as each mask has a predetermined amount of leak at a specific pressure.  Add to that the tossing and turning during the night, and you will have times that you might cause a larger leak.  As long as 1) you are waking up rested (that is the best gauge!) and 2) you aren't triggering any large leak indicator,  I wouldn't be overly concerned with it...