I had the same problem last week that if you chose a category, you should see more items than were displayed.
The issue in my case was related to the WPML settings, some portfolios and categories that are not translated in all languages, were missing.
So if you are using WPML and having trouble displaying portfolio categories, check the settings. Hope this helps someone.
- This reply was modified 5 days, 19 hours ago by squadhouse.