Wow, I actually had a detailed response worked out for you but the damn forum AUTO LOGGED me out so I lost IT ALL!! Sorry, just don't have the time right now to repost it but I am attaching some MPC files of a recent project I just ran and it was split across two project boards.
I have run well over 125 cabinets projects just like this one so I would say I have a fair amount of experience splitting projects across boards and getting things to line up. Take a look at the files and let me know if there is specific questions you have... Once I cool down a little and feel like I can type out my process again, I will ;)
Attachment 65951
Attachment 65952
Attachment 65953
The image is of the finished project.