Open extension marketplace panel, find and install (S)quirrel language support extension;
Open settings window (Ctrl+<,>) and find Extensions/(S)quirrel section;
Setup path to static code analyzer Squirrel/Syntax Checker/File Name executable, which default value is sq3_static_analyzer-dev. Note: you can setup name of environment variable that contains pat, either full path to file or short file name that should be discoverable by system PATH environment variable;
Setup path to the squirrel code runner Squirrel/Code Runner/File Name executable, with default value csq-dev. Note: you can also use name of the environmental variable, full path or short file name;
You are ready to go;
Some hints on usage
Start typing identifier name finishing with = symbol. If this key is known tou will get list of appropriate substitution values;
Set cursor to require() method argument with module path and press F12. If module found it will be opened in new tab;
Type require(" with some known characters of module file name and press Ctrl+ to get list of paths to suitable files from workspace;
Save document to run code checker. All found code errors will be displayed at common Problems panel;
Create or open document from disk and press Ctrl+ to run it. Found compile time or run time errors will be displayed at Problems pabel. All output will be displayed and highlighted at Output panel;