'AllowAddressLookup' registry value is not installed by default and is something that was most likely added manually at some point. Unfortunately i do not have any info on what other customizations were done to the registry on BES machine and would additionally check the follwing:
UseUserAddressBook
HostedServer
LDAPSearch
LDAPALPSearch
LDAPCompanyField
I would recommend to remove any of the above values if found. Please see
Access Denied for more details
I also suspect that re-creation of BB profiles may help to resolve GAL problem.
Additionally i suggest to take this problem offline and resolve it through support case(support@zimbra.com)