What you are going to have to do is make a function.
What it will do is convert, World Location to Relative Location
Example, if World Location is 500/0/0 and you want 600/0/0, you Relative Location should be 100/0/0.
So you need to work out the first location, Find out where the next one should be in world location. Minus that and that might get you your Relative Location.
As a guess, but try that.