is the clay and peblet foundations bugged? If not, how do you use them?

[MythN7]

I am trying to use these types of foundations at the ground level, and 9 of 10 times, any of them that are CLEARLY!! touching the ground are not supported BY!!!! the ground, ONLY the one that started it all.
But there is the RARE! time that one touching the ground does act like a core supporter linked to the ground.

Here is an example from a base im building, I brought clover angled roofs down from my oad tree base, and am trying to make a small sturdy platform of which the ramp is linked to, so it counts as a ground connection incase i lose the upper part holding the ramp.

ANY!!! wooden scaffold works just great, it touches any ground ever, its supported.
But placing these peblet ones down, you can see in the pic, the one 2 tiles away from the finished angled roof allows to start dumping mats in, so yes it counts as supprted, but the one beside it linked to the ghost roof, will poof away if i cancle the roof.
The peblet one under that one that is like 90% burried in the gound is not supported by the ground and wont let me put stones in, nor the one like 85% burried in ground under the ghost roof, wont let me put stones in there either.
I put a wood scafold beside linked to the snapping grid to show that yes it works fine.

also, i can place any peblet foundation in these said spots if its a hair out of snapping reach so its tech starting a new structure, which im not sure would count as supporting other things build on top that sorta touch but not SNAP!! place touched.
https://steamcommunity.com/sharedfiles/filedetails/?id=2868077813

So in a nut shell, how do you use these non wood foundations that are clearly touching the ground, but will crumble if random other ones get destroyed?

[Artok]

I've also used them and noticed what you mention : "non-buildable" foundation.

I've stopped using these foundations as they are too weak.

I've build a lot of ramps as your. I start on a wall or half-wall. Packing both ends with walls, as one single piece is quickly destroyed.

On this screen you see that I replaced grass walls with brick walls
https://steamcommunity.com/sharedfiles/filedetails/?id=2868367686