Skyboxnight in TE / Data / Pak1 / Data / Models / Texture, add that file in that folder and if you play with voullez night must rename skybox.jpg, here to the sky, and close enrregister
For Courttexmelnuit, open TE / Mods / ITST116 / Data / pak3 / Data / Customcourt (6 or 7 or 8 those corresponding to short 3 Melbourne choice) and to replace courttex, think rename courttex not courttexmelnuit . This is done, close and enrregister
For Courta01melnuit, open TE / Mods / ITST116 / Data / pak3 / Data / Models / Texture / Stadium / Melb, add there and think rename courta01.jpg is Done!
think back all 3 game files you have changed by renaming them with day instead of night, so you can change day and night as you see fit!