Install Real VNC Viewer on the Windows machine, connect the Pi to your home network and run everything on the Pi4 it is more than capable. You can also put Real VNC Viewer on your phone or tablet & monitor the progress there if you like.

I personally found that the guiding performance wasn’t as good when using it as a server client set up due to lag over the network, unless I ran PHD2 directly on the Pi via the ST4 cable. But that’s a bit of extra work to start PHD2 before you connect the server, again this can be done over VNC if needed.

I found I don’t need a static IP on the network just use the address shown in the Stellarmate tutorial video Stellarmate.local I think from memory.

At least doing it this way you’ll get results.

Try it first with the simulators, then connect the other equipment 1 item at a time and make sure it works before saving the configuration, then shutting down and restarting the Pi before connecting the next item. Doing things this way helps isolate problems with an individual piece of kit.

Good Luck