Light example

//x3,1,#test,22[5]2:255:0:0[7]%,y,,1.1.1
// Above is your LOAD LINE. Copy it into Visual Script Builder to load your script.
// dco.pe/vsb

void Main(string argument)
{
  // block declarations
  string ERR_TXT = "";
  List<IMyTerminalBlock> v0 = new List<IMyTerminalBlock>();
  if(GridTerminalSystem.GetBlockGroupWithName("test") != null) {
    GridTerminalSystem.GetBlockGroupWithName("test").GetBlocksOfType<IMyInteriorLight>(v0, filterThis);
    if(v0.Count == 0) {
      ERR_TXT += "group test has no Interior Light blocks\n";
    }
  }
  else {
    ERR_TXT += "group test not found\n";
  }

  // display errors
  if(ERR_TXT != "") {
    Echo("Script Errors:\n"+ERR_TXT+"(make sure block ownership is set correctly)");
    return;
  }
  else {Echo("");}

  // logic
  foreach(IMyInteriorLight interiorLight in v0) {
    interiorLight.Color = new Color(255, 0, 0);
  }
}

bool filterThis(IMyTerminalBlock block) {
  return block.CubeGrid == Me.CubeGrid;
}