Hi,
I've encountered the same issue. I'm trying to get all site-to-site site vpn traffic (the return traffic as well) to route via an interface group (two simultaneous tunnels) and not the routing table.
I assigned each tunnel an interface and set a rule on the lan to use the gateway group for all traffic destined to the opposing site.
The problem is that if one tunnel goes down, and its the one in the routing table, the return traffic gets lost.
Any pointers on how I can get it working?
Thanks,
E