PC Disconnects from Network while Sleeping

I am trying to figure out a solution for every computer at my company. I recently assembled 6 computers and we have installed them to use. All the computers share files through our server including the licensing of a design software every computer uses. The problem is one of the guys will open the software on their computer to make adjustments to a design and then go run the changes on a machine. The computer falls asleep while they do this obviously as it can be anywhere from a couple minutes to hours. When they come back they receive error message saying something along the lines of something happened with windows and the program must be closed. Also as the day progresses they cannot even open the program the first time, but restarting their computer will allow them to access the software without any issues. Every search has come up with turning off NIC power management, but that is not an option on these computers. I have looked through the BIOS and have not found an option there either. They all have static IP addresses if that matters.

So I fully believe that should solve issues. Unfortunately my response to that solution is simply "because my boss doesn't want them to." So I was trying to find a different solution here for the same result before trying to convince him this is the way it will have to be.

Sounds like a 3rd party solution ($$) is required for a specialized situation. The NIC manufacturer/support may already have a solution ($) for a similar situation. As a reach, the software vendor might have a solution ($) to prevent hardware time-outs from having such a devastating effect.