Lost changes after up dating from version 4 to version 6 Simanswers.

Hi Mike hope your well.
I seemed to have lost all the css changes i made while updating from version 4 to 6. I'm guessing all the changes i made were wiped so i'll have to do them again. Is there a way to make changes that will not overwrite when updating for next time?

It also seems like the categories are not working as well. Is there a module or plugin i should be updating?


Many Thanks Neil