Is there any trick to using categories on Arc Hub?

[NikkiHill]

I am trying to put my Open Data into categories and my tags/groups are not pulling under the categories. I have tagged my dta as well as put them into groups, but nothing seems to work after I view the page. 

[KateAulman]

I have this question too.  I have created a new group, made it open with public sharing, added public content to it.  When I try and use it in Hub in a Category, in Settings/Use Group it is not listed.  I cannot see how it differs from the group that does show up.  Help!