For a VPN to work properly it has to be as if your machine is on that other network. If you were able to do what you wanted this means there is a flaw in the VPN and it will soon be fixed.
Some folk have a very hard time understanding why this is but that's the reason for the VPN. To stop leaks. What you are trying to do is to make the VPN leak!
I have a pc that can connect to my corporation over a vpn. I also have gotomypc installed on the same machine. I can connect with no problem on a remote pc if the vpn is not connected however I cannot connect if the vpn is connected. If I connect without the vpn everything is good until i connect to the corporation and the connection freezes. I have 30 mps down and 3 mps up so overall speed is not the problem. When I do a speed test on the internet with sites like speakeasy I get 30 mps without being connected to the vpn but only 3 mps when i'm connected to the corp. I have tried limiting packet sizes, and i have setup gotomypc to connect over a second network adapter. I still get the same results. Any suggestions? Thanks,