Is your objective to allow the SME to monitor/control the internet traffic for the PC, or just to allow the PC to connect to the SME and still browse the Internet?
If the latter, you need only disable "use default gateway on remote network" in the properties of the VPN connection on your workstation (Open the "Properties" of your VPN connection, Select "Network", Select "Internet Protocol (TCP/IP)", Select "Advanced", remove check-mark for "Use Default Gateway on Remote Network").
If the former, what happens if you set the PC to use the SME as a proxy server?