Error while using director class

I am trying my first application in corona using director class but facing problem in my initial code here’s my code:
 
 

        

\_W=display.contentWidth \_H=display.contentHeight         local director = require("director")                  local mainGroup = display.newGroup()                           local main = function ()                      mainGroup:insert(director.directorView)                      director.changeScene("splashscreen")                                   return true         end          main()  

And here is my splashscreen code:

    module(...,package.seall)              function new()         local localGroup =display.newGroup ( );              local bgImage= display.newImageRect ( "splash\_screen\_images.png", \_W, \_H );         bgImage:setReferencePoint(display.CentreRefrencePoint);         bgImage.x=\_W/2;         bgImage.y=\_H/2;                  localGroup:insert(bgImage);              local delayTimer=timer.performWithDelay ( 3000, changeScreen, 1 )              local function changeScreen1                 director:changeScene("meuscreen");                 timer.cancel ( delayTimer );         end              return localGroup              end  

I am not able to run this code, always getting this errors;

Director Error : The scene name must be a string. scene = nil

Try storyboard or composer, which are scene management tools created by Corona labs. Director can be a bit old and uses not suggested module.

Try storyboard or composer, which are scene management tools created by Corona labs. Director can be a bit old and uses not suggested module.