It wasn't really removed (yet - it might be in the next version) but Activities aren't working as expected. If you can't use the old pst that holds the journaled items, open it in Outlook and MOVE the items to the new journal folder (use Folder list - Ctrl+6 - to see the journal folder).
Set a list view on the journal, select all (Ctrl+A) then use move to folder command and select the new journal folder.