Originally Posted by
jurcek1987
data/worlds/map/campaign/imperial_campaign/descr_strat
at the start of the file you have a list of playable and then unplayable factions. Put kantakouzenos among the playable factions.
and then open data/descr_sm_factions, and you'll find "byzantium, shadowed_by kantakouzenos" and "kantakouzenos, shadowing byzantium". These two should then be changed to the other way around. This should do it if I'm not mistaken.
To become emperor as kantakouzenos, regency will have to practically be destroyed (less than 3 settlements), and of course you need Constantinople