After running into some initial connection errors (which were resolved via Watchguard Firewall - Issues with SSLVPN), I'm able to accept the SSL certificate provided by the firewall and get further into the connection process / attempt.
However, I'm still unable to complete the connection, and I'm currently seeing the following in the client log
2013-06-28T09:12:06.375 OVPN:>LOG:1372425126,,438 variation(s) on previous 20 message(s) suppressed by --mute
2013-06-28T09:12:06.377 OVPN:>LOG:1372425126,I,SIGTERM received, sending exit notification to peer
2013-06-28T09:12:06.379 OVPN:>LOG:1372425126,D,TIMER: coarse timer wakeup 1 seconds
2013-06-28T09:12:06.382 OVPN:>LOG:1372425126,D,TLS: tls_multi_process: i=0 state=S_PRE_START, mysid=3492fe15 883900f2, stored-sid=00000000 00000000, stored-ip=184.174.143.176:443
2013-06-28T09:12:06.385 OVPN:>LOG:1372425126,D,TLS: tls_process: chg=0 ks=S_PRE_START lame=S_UNDEF to_link->len=0 wakeup=604800
2013-06-28T09:12:06.388 OVPN:>LOG:1372425126,D,ACK reliable_can_send active=1 current=0 : [1] 0
2013-06-28T09:12:06.390 OVPN:>LOG:1372425126,D,ACK reliable_send_timeout 1 [1] 0
2013-06-28T09:12:06.392 OVPN:>LOG:1372425126,D,TLS: tls_process: timeout set to 1
2013-06-28T09:12:06.394 OVPN:>LOG:1372425126,D,TLS: tls_multi_process: i=1 state=S_INITIAL, mysid=bc742126 a86ff11a, stored-sid=00000000 00000000, stored-ip=[undef]
2013-06-28T09:12:06.397 OVPN:>LOG:1372425126,D,TLS: tls_multi_process: i=2 state=S_UNDEF, mysid=00000000 00000000, stored-sid=00000000 00000000, stored-ip=[undef]
2013-06-28T09:12:06.399 OVPN:>LOG:1372425126,D,SENT OCC_EXIT
2013-06-28T09:12:06.402 OVPN:>LOG:1372425126,D,TLS Warning: no data channel send key available: [key#0 state=S_PRE_START id=0 sid=00000000 00000000] [key#1 state=S_UNDEF id=0 sid=00000000 00000000] [key#2 state=S_UNDEF id=0 sid=00000000 00000000]
2013-06-28T09:12:06.404 OVPN:>LOG:1372425126,D,RANDOM USEC=230951
2013-06-28T09:12:06.407 OVPN:>LOG:1372425126,D,WE_CTL n=0 ev=0x004ccf2c rwflags=0x0001 arg=0x004775e4
2013-06-28T09:12:06.409 OVPN:>LOG:1372425126,D,WE_CTL n=1 ev=0x004c6f74 rwflags=0x0003 arg=0x004775f0
2013-06-28T09:12:06.411 OVPN:>LOG:1372425126,D,I/O WAIT T?|T?|SRQ|Sw1 [1/230951]
2013-06-28T09:12:06.414 OVPN:>LOG:1372425126,D,WE_WAIT enter n=3 to=1231
2013-06-28T09:12:06.416 OVPN:>LOG:1372425126,D,[0] ev=0x00000134 rwflags=0x0001 arg=0x004775e4
2013-06-28T09:12:06.419 OVPN:>LOG:1372425126,D,[1] ev=0x000000a0 rwflags=0x0002 arg=0x004775f0
2013-06-28T09:12:06.421 OVPN:>LOG:1372425126,D,[2] ev=0x0000011c rwflags=0x0001 arg=0x004775f0
2013-06-28T09:12:06.424 OVPN:>LOG:1372425126,D,WE_WAIT leave [1,0] rwflags=0x0002 arg=0x004775f0
2013-06-28T09:12:06.426 OVPN:>LOG:1372425126,D, event_wait returned 1
2013-06-28T09:12:06.428 OVPN:>LOG:1372425126,,NOTE: --mute triggered...
This was suggested in a comment in the earlier question (before I decided to break this out into a separate question):
The updated log looks like it's an issue with the ISATAP on the client. In the Watchguard System Manager if you open up your policy manager -> VPN menu -> Mobile VPN -> SSL verify the primary and/or backup firebox IP addresses and the virtual IP address pool the clients use
I've actually been using the Web GUI to configure the Firewall / setup the VPN (not the Watchguard System Manager, although I'm slowly becoming vaguely familiar with it).
I did check the Web GUI, and can confirm the IP address (for the primary Watchguard connection) is correct, as well as the virtual IP address pool (which is set to 10.1.10.176/28).
I have noticed that I'm unable to download the VPN client via the public IP address:4100/sslvpn.html (which I'm supposedly supposed to be able to do from the outside). That said, I pulled down the client & client config manually a couple days ago using these instructions: http://www.watchguard.com/help/docs/wsm/11_XTM/en-US/Content/en-US/mvpn/ssl/mvpn_ssl_manual-distribution_c.html).
Using those same instructions today, I updated the client config (just in case there were settings that have been changed) - so going through the System Manager, I pulled down the support files, uncompressed them, grabbed the sslvpn-client.wgssl file, and ran it on the client computer from an outside IP address trying to connect to the VPN.
I continue to get the error messages above.
Any additional thoughts on this?