I don't really understand what you're asking. Here's what I see the situation as:
A customer is using a laptop at work, and on that laptop the customer is using your app with TurboFloat Library connecting to a TFS instance on the work network?
Is that right so far?
And from that you want to know what happens when a customer bring that work laptop home, correct?
Did I get all of that right? If so, then the answer is pretty straight forward: either configure the TurboFloat Server to allow connections from specific whitelisted IPs (e.g. the customer's home), or have the customer use a VPN to access the work network.