I will only use the Track Editor for this and MAKEITGOOD.
It will be composed of 4 races of increasing difficulty (easy, medium, hard and extreme) which can only be unlocked, in solo mode, when the cup will be won.
So I'm creating this thread in the hope of getting some help with the difficulties I'm having.
First Track : Gardening Paradise.
Almost finished, I have two difficulties :

The texture of the faucet and the back of the automatic watering is the same as that of the ground.
It seems that I cannot modify their texture without changing part of that of the ground.
You confirm ?
The second problem concerns the file "properties.txt.
None of the changes I make have any effects in the game (apart from the gravity that I was able to modify successfully for my second track : Space Opera). I conclude that I use it badly!
What i would like to get :
As the race takes place on wet grass, I would like to have a feeling of heavy driving with slight skidding in the turns.
what I do :
I select the ID 12 : Grass and I modify the properties "roughness, grid and hardness",
but nothing changes in the game.
Does anyone have a solution ?
Thanks in advance.