You can't use entity:Move for the character, it's only for non physical objects because it ignores collision. For character, you use enitity:SetInput. Look how character is done in FPS example project. You can also see how walls and platforms are set up there.
self.entity:SetInput(self.camRotation.y, playerMovement.z, playerMovement.x, jump , false, 1.0, 0.5, true)
https://www.leadwerks.com/learn?page=API-Reference_Object_Entity_SetInput
You don't need to do SetGravityMode, all you need is static boxes with scene type and correct character movement script.