Oh! It looks like you forgot to enable permissions to submit to the group. Right now only the 'featured' folder is open to submissions.
Here is how to change the settings (in case you didn't know; better safe than sorry ^^)
Go to the 'Admin Area' on the front page of the group (I think it's at the top, can't remember), then in there, on the left-hand side bar, click on 'Manage Members'.
From there, you'll see a list of all the people in the group, separated by tabs. Click on "members".
On the right side you'll see a scroll box. Inside there are your permissions, like admin privileges, front page layout, favorites, and then the gallery.
Underneath "On Gallery, Members:", click on 'Show All Folders'. from there you'll see all the folders you have opened in the group. After that it should be pretty self-explanatory. ^^
I'm really sorry if you know all this already, I just want to help :'D
Oh, and make sure the folder-specific limit is selected to be 'Unlimited', and turn off submissions from members to the featured folder, if you want to manage that one yourself.