@Robert Doe Adding answer here for reference from the Github.
It looks like the root of this issue is to do with a Dependency on the Simulator node-sass which uses the node-gyp package to compile various parts of the Simulator. It is expecting Python2.7 and VS 2017 C++ Tools to be installed and available somewhere on the path (or in the directories eg C:/Python27 or the VS default install dir)
As a workaround for now, the following should suffice:
Install Python2.7 (https://www.python.org/download/releases/2.7/)
Confirm VS 2017 Visual C++ Build tools is installed (This can be found at: https://visualstudio.microsoft.com/thank-you-downloading-visual-studio/?sku=BuildTools&rel=15)
Re-run the command npm ci && npm run build
Let me know if this functions for you! I replicated this on a Virtual Machine and these were the steps required. I'll close off this issue in 2 weeks If I don't hear back.
Future fixes should remove the simulators dependency on node-sass as this has now been deprecated per: https://www.npmjs.com/package/node-sass. Will look into Simulators' build and consider if a PR is required to remove this deprecated dependency.
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