Raybounce returning empty element list

Hi,

I am playing with raybounce technique to check for my height clearances.
But the problem is, the raybounce element list returns empty list but it can get the element wall list. I am hoping to get the ceiling element as part of the list, but it will always return as empty.
Did i miss something in my definition?

Thanks.

To add, ceiling element was turn on (ignore the off-preview on the attached screenshot of my dynamo definition).

Did you ever figure it out? I’m experiencing the same thing.