Thanks for getting back to me so quickly! There are 50 categories, not sure where 3000 came from...
Like I said in my original post I have "Display Members Gallery on the main index page?" set to yes in the admin settings, I have turned it off and turned it on again and still no luck.
I can see the usergalleries using the link you sent, but when you click on any of the users you get the error saying you do not have permission to view this category. This message shows up if you are registered and logged on and ever if it is your own user gallery you are trying to view!
I just updated tonight to the newly released version by copying all the files over the top of what I already had there and setting up the config file again, so in effect a fresh install, and the problems are still occurring.