Here are the steps to set up Visual Studio Code for Space Engineers ingame script development.
This will provide an environment where autocompletion / intelisense and syntax checking work.
I'll assume you already have SE installed!
Install Visual Studio Code (VSC)
Install the following VSC Extensions
install .net cli tools / SDK (needed?)
install net framwork devpack 4.6.1
Then clone this directory structure.
If you have a non-standard SE location, change SpaceEngineers.csproj
'open folder' (this folder) from VSC.
copy starter-template.cs
to a new file for each script you create
change the namespace
Put your code changes between the region tags (see comment in template)
Credit to https://github.com/mrdaemon for the working .csproj
file.