Hellp Brian,
I am not going to go into to much depth on this as it Will make everyone go to sleep
...
CV Is not a simple connect both lines, It will run as many as 1000 lines at the same time to make the moves go at the programed feedrate. The smaller the moves (less steps) the less it can blend the move smoothly. The more steps (resolution) the smoother the operation will be.
I don't understand why you are running inch files in MM mode but it is your machine and you can do what you like
I like to keep the scaling and so on in the Cam system and keep the machine with the same settings (this is how it is done in 99.99% of installations). As for not backing up your settings in the XML, All I can tell you is that the program was never designed to operate in the manner that you are asking it to.. Sorry for the trouble.
Thanks
Brian