The mod works fine on 1.8.6, so it's something you are doing wrong..
1 - verify the module s loaded ( /os modinfo cs_accessfounder )
2 - verify the user s on the access list with the correct level ( /cs access #chan list )
3 - ensure the user is authenticated with nickserv before /hopping or /joining ( /ns status <nick> must return 3)
And if it still don't work, check for modules that might be causing issues.. ( paste /os modlist )