Don't use Profile Paths in Active Directory Users and Computers. It's a very old Roaming Profile method from Win NT and has been replaced with GPO Folder Redirection.
1) Remove all the profile paths from AD Users & Computers, leave this field blank
2) Create AD folders to separate users into logical/physical groups to which you will apply Group Policy Objects
3) Open the Group Policy Editor, create a GPO that applies to the user folder in question, and use the Users Folder Redirection settings to send/create their profiles in the right SMB share.
Note: Make sure your SMB share has the right permissions. There's some slightly complex things where you need to set CREATOR to have Full Control but USERS not to have any control past creating folders in the main folder (ie each user (CREATOR) should have Full Control over their files, but all users (DOMAIN USERS) should only have access to create their profile folder, not access to other user's profiles).
FYI, If you have Win8 computers on the network, you can install RSAT on one, copy their GPO definitions into the DC GPO share, and use it to maintain your GPO. That way you'll have the latest available copy of all the GPO settings.