Hi,
Outlook 2013 uses a new security model that disables addins. Hence the addin needs to be updated, and you need a further DLL file that bypasses the Outlook Security Manager.
If you are interested I can re-write the add-in from scratch for you and ensure that it works, but it will take me upto 5 days to complete the job.
Good quality work done. Support assured.
Bests,
Steve