Not sure how much help it will be since it’s also explained in Illustrator, but i did explain the process slightly differently here:
This method uses the freebie indexing sticks file in the first post of the thread, instead of a disposable side jig.
You might have some trouble cutting the thing into parts with Inkscape since I think it tries to close paths, but I’m not that familiar with it…it will probably involve a lot of Break Group functions on it. But whatever size you decide you want to set up your sections (under 10", which is the limit now), be sure to process a set of the index marks before each phase when you run it in the GFUI. Everything else needs to be set to ignore when you score the index marks, then process one section, then shift the board up, then process index marks, then process another section, then shift the board up…etc. Always align the marks when you shift it and you should get a pretty good result. (And you align them with your eyes, on the material on the bed, not the camera or the interface.)
Good luck! (Try something simple first like the one I demo’ed)