I did not have too many, but can I remember a work-around that I think I used.
This may not be the one that worked [when traveling, I always remember the route to how I got lost and end up getting lost again]
I set up a new drawing using styles, model info, ect to get it how I like, I than used Mass Materials Importer to get them into the drawing, Save as template, use for default. Then one by one over time, when I used one of them in my models I saved them into my materials folder. It means you have to use colours in models a lot for a while and it's annoying if you purge your drawing and then need one that you haven't moved, but you can always open a new drawing from templates and import the model over.
anyway without being able to check my memory...