How to set a rigid body to slide downwards on another tilted rigid body in Isaac SIM?

I have added material properties to two objects, including dynamic friction and static friction. Even if the friction force is set to 0, one object cannot slide on another tilted object。

It is really hard for me to debug this setup without access to the original USD/USDA files. Would you mind sharing the scene?

From the error messages (that I can see in your recording that you so kindly shared) I can gather that the joints of the articulation have not been properly defined, but I’m not certain that this is the issue.