MultiWAN and multisite tunnel

[Bodanel]

Hello all

my network diagram is attached to this post.
Current setup is this:  We have a layer 2 connection between branches and HQ with a OpenVPN tunnel to encrypt traffic and another connection with a OpenVPN tunnel over the internet. So each branch has 2 connections with some sort of load balancing (some script which add some custom routes to the routing table)

Basically what i want is this:
1. connect the branches to HQ
2. have the traffic between branches and HQ encrypted - for this I thought OpenVPN site to site
3. have fail-over and load-balancing

I dont know if this is possible with pfSense altough documentation indicate this option but I havent been able to setup (multiwan was easy to setup but this i'm haven't been able to put it on).  If there is something on the gold membership that could help me setup this I will pay it glandly.

Thks in advance for any pointers.