Check the editor I just recommended, but I don't think it has a convoy editor nor do I think an easy one exists, but google can help you with that. And yes to the DLC question.So Fates is easier to edit than Awakening? Can I at least find a good convoy editor for that game (since I had to give myself every item in that game, including illegal/useless stuff, just to replace all the items I lost, just because I tried to clone an extra unit, just to add Gaius to my party, because no one told me he would be gone forever and that he was even recruitable.)?
But getting back to this DLC, I won't be able to load my Revelation save file, until I reinstall the same cia I originally used to install the official DLC in the first place, on top of the custom DLC I just installed?