I don’t understand which you mean by Category ID. Is the internal ID number of the category from which to take the posts of the user into account?
It should be much useful to be able to select several categories by its name, like in topic thumbnails TC.
It would be great to let each user to select from which categories he wants to show messages in his portfolio, overriding general default (if the admin allows it).
Another great improvement would be to add an option to let the admins select in the Component config which user groups can have a portfolio (based in level, or whatever admins stimate).
Another great addition It will be a great way to create a personal gallery not just from posts in has published in a category.
To get that, some kind of per user private category should be implemented, where users can create their posts and show them in the profile.