Shape point or markers moving with Model while changing transform

[picare]

Hi,
In a project, I have markers, created with python, with no projections, just a relative XYZ to the model (center of a cylinder for example)
When I move the chunk with the helps of camera positions, or if i align the chunk with another chunk, the markers are not following and stay at the original place, not longer in the center of the cylinder.

I tried to convert the markers to point shape, successfully, but the shapes are also not following the model, when modifying the transform.

Any idea to keep markers or points shapes linked with the model ?

regards,
Pierre