Regarding the FWSM, you can issue the 'no failover active' command on the Active box or 'failover active' on the Standby box to force failover.
For the IDSM, you can manipulate the spanning tree cost on the active IDSM-2 module (making it higher), so that the secondary module becomes the primary traffic path. Sometimes this automatically happens after the FWSM failover (because of SPT cost change), but this would depend on your spanning tree topology. This can be done via the intrusion-detection comand on the host switch chassis.
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...