After Tumbleweed update 20160921 NetworkManager does not read properly the
custom IPv4 routing.

The connection to the VPN fails with an error "IP settings not correct" or
similar.

The only way to get it working is to remove all custom routes and settings. 

>From Snapper I see this was changed in config, apparently the new plugin does
not handle the old config properly:

--- /.snapshots/20/snapshot/etc/NetworkManager/VPN/nm-openconnect-service.name 
  2016-09-03 00:59:23.000000000 +0200
+++ /.snapshots/21/snapshot/etc/NetworkManager/VPN/nm-openconnect-service.name 
  2016-09-22 02:15:07.000000000 +0200
@@ -1,7 +1,13 @@
+# This file is obsoleted by a file in /usr/lib/NetworkManager/VPN
+
 [VPN Connection]
 name=openconnect
 service=org.freedesktop.NetworkManager.openconnect
 program=/usr/lib/nm-openconnect-service
+supports-multiple-connections=true
+
+[libnm]
+plugin=/usr/lib64/NetworkManager/libnm-vpn-plugin-openconnect.so

 [GNOME]
 auth-dialog=/usr/lib/nm-openconnect-auth-dialog