At startup you will be presented a 'Controllers' page. You will need two instances, one for external network and one for internal network (assuming wireless access).
Hit the '+' icon to add a controller. On the 'Add Controller' page you will have several data fields.
For external network access:
Host: (enter your dyndns info, i.e. xxxxxxx.dyndns.org)
Port: (standard is 80, but it is recomended to use a non-standard port. Needs to match the port forward rule used in your router)
User: (Apex username)
Password: (Apex password)
For internal network access:
Host: (enter the internal network ip address, I use a static address)
The rest is the same.
Todd