I use a netgear 2440 box with pfsense for another openVPN instance, but the PFsense software handles the server and client certificate management. I can export an openvpn config file for my client computer and it works fine.
The device I am using now:
http://www.microhardcorp.com/BulletCAT9.php
Just lets me import certificates and keys.
Using windows 10 unfortunately as my client computer but no other option.
Thanks
mrtrent