Hello @AlexBV
We need to divide and conquer, to figure out if the issue is with the OGR datasource, the data itself, Delphi (unlikely), or the OCX. We recently discovered a bug in the OCX related to 3D data, although that applied to disk-based Shapefiles. By the way, what is the OGR datasource?
One thing to try would be to load the layer into memory (do not yet add it to the Map) and then get the Shapefile version of the layer (using GetBuffer). Then try adding the resulting Shapefile to the map to see if it behaves any differently.
Then try saving the Shapefile to disk (using SaveAs). You can try loading it from disk, understanding that there may be issues related to load due to the bug. If you don’t mind posting the Shapefile, please do so, and I can try loading it to see what the result may be (I am currently running a version of the OCX with the bug fix, but I have not yet posted it).
Let’s start with these things and then decide where to go from there.
Kind regards,
Jerry.