I have an unusual issue.  My work requires I first connect to the company VPN, and then to a Cisco AnyConnect VPN to access other tools.  With the ER605 having VPN passthough on my default, all used to work fine.  Then sometime last year, I find that some sites and apps that once worked over AnyConnect no longer do. My solution was to add a second router (A NetGear in this case) that connects to the same ER605.  It seems to only fail getting do a small (but important) number of svcs on the work network, and only when AnyConnect is engaged.  

I don't do anything special with this ER605 other than assign static IPs on the LAN.  I've tried putting the PC in the DMZ without success.  Even tried putting the ER605 to factory defaults once, and still no luck.  Our engineers didn't have a solution except to suggest adding a second router on the DMZ.  The DMZ didn't seem to matter though, I've disabled it and the second router still functions fine.

As I have a working solution, I'm loathe to blame anything outside of my LAN.  Typically I'd include all the specs and firmware info, but really I'm just interested in anyone's thoughts  on why adding a second router between the PC and ER605 vs a direct connection to the ER605 would be actually be a solution.