Windows 7: Anyone with experience connecting Heim GSS to a Windows 7 laptop

I have an odd LAN connection issue and I'm hoping someone out there has experience with this unique hardware. I appreciate helpful responses, but if you don't know what a Heim is, please take an extra second to review your response before posting.

I have an HP laptop with Windows 7 Enterprise x64 on it. I'm connecting via a standard Cat-5e cable to a Heim GSS link mod. The link mod has a standard IP address of 11.59.19.202. So, I've set a static IP on the laptop of 11.59.19.10, subnet 255.255.255.0, with no default gateway and also no DNS server, and I've connected the two. Windows detects the connection, and after a while the network access is there, and I can ping the device and run the software I need to capture and record telemetry data.

After I shut everything down and come back the next day, Windows is no longer able to connect to the link mod. I get the dreaded unidentified network error.

Under Vista Enterprise x64 on the same laptop, there were no issues at all. There's no security software installed, no antivirus, and no HP software other than the drivers downloaded from HP. This is a completely stand-alone laptop that will never be connected to any external network.

This particular issue has got me stumped. This is a pretty specific issue, but I hope someone other than me has tried using a Heim with Windows 7.