There isn't too much difference between Windows 11 and Windows Server 2022. Either should work fine for hosting the WebServer on a dedicated PC. The choice is mostly preference rather than functionality. For extreme hardware situations, such as installing 2 TB of RAM (~2048 GB), Windows Server would work better. But that is unlikely to apply to your case.
Windows Server has a couple variants: Windows Server Core and Windows Server Nano. If you run with Core, you won't be able to stream from the Webserver because you won't be able to get a Graphics Context. If you run with Nano, FlexSim won't launch at all; its dependencies cannot be installed on Nano.
FlexSim is a fully 3D simulation software environment. FlexSim can be used to simulate any process in any industry.
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