Here is how I enabled WPA2 Enterprise with Radius.
Using Winbox -
1. Go to Wireless->Security Profiles. Create a new security profile.
- a. Under the General tab, select Mode=dynamic keys, Authentication Types - only WPA2 EAP (deselect WPA PSK and WPA2 PSK), Unicast Chiper - only aes ccm, Group Chipers - only aes, Enter your Supplicant Identity, Management Protection=Allowed.
b. Under the Radius Tab, Select MAC accounting (as I wanted accouting based on MAC), MAC Mode = as username, MAC Caching time = disabled.
c. Under the EAP Tab, EAP Methods=Passthrough, TLS Mode=no certificates, TLS Certificate=none
2. Under the Radius Menu, Add a new server. Selecte Service - only Wireless, Enter the Radius Server IP Address, and Secret (you need to enter what has been entered in your RADIUS server)
3. Go to Wireless, select the interface, and set the Security profile to the one created in step #1
I configured mine based on http://forum.mikrotik.com/viewtopic.php?f=7&t=23185