yes , of course you can! Here is the howto:
First get your public IP.
Then DMZ forward your connection to the pc running the controller software.
Then login and set units to connect to IP you forwarded to your DMZ
Use SSH to manually point the AP to the Controller
For this step you will have to determine the DHCP address the AP acquired. There a many ways to do this and I am no going to cover them in my instructions.
Once you have found the DHCP address use a tool like Putty to establish an SSH connection to the AP. The default credentials are
Username = ubnt
Password = ubnt
Enter the following commands where ip-of-controller is the IP of your controller
mca-cli
set-inform http://ip-of-controller:8080/inform
The AP will reboot.
Login Again , and enter the following command a second time
set-inform http://ip-of-controller:8080/inform
Go to your Controller and the AP should now be showing under the Pending tab.
Hope this helps!
Ted