To answer my own issue, I now think I know the cause of the OpenGL view jittering issue, and have a workaround
I believe after testing that the distant origin issue does not require that any objects are (or have been) far from the project origin. What is required is the CAMERA in use has been defined far from the project origin.
I suspect that there is a default camera position which is defined when the project is first generated (even though there is no explicit camera object), and that this does not move even when the viewpoint you see while navigating in 3D openGL window moves.
By explicitly
moving the camera position close to the object being viewed (rather than just flying or zooming/panning your viewpoint there), the problem goes away. (this can be done in 3D projection settings)
The issue in my case arose I think when I imported survey data to create my site terrain, and the surveyors data appeared far from the project origin (and the default camera position).
Moving the project origin close to the imported objects, and clicking 'fit all' in 3D window (or otherwise flying the openGL viewpoint to the distant objects) meant the 3D view point calculated in openGL *seemed* normal, but was getting rounding errors due to large offset distance from initial/default camera location still in use.
The missing cursor issue in object dialogs and pallets remains for me at least, but at least one mystery solved.
PAUL KING | https://www.prime.net.nz
ArchiCAD 8-28 | Twinmotion 2024
Windoze 11 PC | Intel Core i9 10900K | Nvidia Gforce RTX 3080 | 32 Gb DDR3 | 2x4K monitor extended desktop