I tried to figured out whether it is possible to add new company logos during a game save, because it's always the case that before starting the game I'm not sure how things develop so I can't really predict how much and which logos I will need for my subsidiaries. Using the same logo like the mother company is not possible, so at least I'd like to use copies of that, but not only.
If I add logos to the used mod and expand the dbf file it is not updated in the current save if I load it, so it would be no workaround for that.
A nice and easy way would be to always be able to add logos while the save is running, maybe in a similar way you can do it with pics for product customizitation. In this case you would not have to prepare every logo you might need and batch it into the mod. Very useful for subs.