Hi, Hope you can help!

I'm trying to connect to my Dad's iMac from my Macbook Pro at my home.  Both computers are running 10.7.2....both are intel macs.  I have an airport extreme and my Dad has a Netgear DSG834g.  I installed the slink agent on my Dad's iMac and installed the slink app on my MBP.  I tested on my Dad's network....and everything worked fine...I was able to screen share etc.  I have come home to my network and now can't connect to my Dad's iMac over the internet.  Slink tells me that I am connected to the internet, but my Dad's iMac has refused the connection. I have set my Dad's iMac to "Wake on Demand" I used to able to wake my Dad's iMac when we both ran Snow Leopard and I used Back to my Mac. Any suggestions?

Thanks in advance!

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