Run make_portable.ps1 in Powershell to build a PORTABLE VapourSynth with vseditor-mod and vspreview-mod embedded.
If you need to use your proxy, uncomment the first line and set it to proper value.
You need to put your VapourSynth script module file (*.py) in VapourSynth\vapoursynth64\scripts, and your filter binary file (*.dll) in VapourSynth\vapoursynth64\plugins.
To check if VapourSynth and vspreview are installed properly, you can open the root directory in VSCode and press F5 to launch vspreview, or just run the command below:
VapourSynth\python.exe -m vspreview test.vpya gray gradiants map should be shown.
vseditor locates at VapourSynth\VapourSynthEditor\vsedit.exe, double clik to execute it and content of test.vpy will be shown if everything is correctly installed.