I've had zero luck with QuickVPN and using more then 5 SSL VPN tunnels seems to lockup the SA540. As a workaround I've used Shrewsoft's IPSEC VPN client since it's "free". I've also had luck with The Greenbow IPSEC client. It's a little nicer in that it can run before msgina and runs in the tray, however it does run around $80/client.
Use the VPN Wizard and configure the following:
VPN Type: Remote Access
Connection Name: IPSECRA
PSK: Whatever you like
Local WAN: Dedicatd WAN
Remote GW Type: FQDN
Remote FQDN: remote.com
Local GW Type: IP Address
Local IP Address: WAN IP of SA500
Now you want to add XAUTH to the IKE policy. Since you can't modify an IKE policy bound to an VPN Policy, you need to do the following:
Create a dummy IKE Policy, just enter temp for the name and temp for the PSK and save.
Go into the new IPSECRA VPN Policy and change the IKE Policy to "temp" and save.
Modify the original IKE Policy so XAUTH has "edge device" and Auth Type is "user database" and save.
Return to the VPN Policy and return to the original, just modified IKE Policy and save.
Delete the temp IKE Policy.
Setup users as necessary in IPSEC Users, just ensure you choose the type as "Standard IPSEC (XAUTH).
Download and install Shrewsoft VPN client
Paste the following into a text file and name it "myconnection.vpn".
The main thing that jumps out at me is that you are using XAUTH for authentication of your users. According to the admin guide, you should be using Cisco QuickVPN. I have personally set this up before and it worked flawlessly using this admin guide:
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