OK, so not sure if this is a bug or not but.....
If you place an object, place the camera at it's position, move the camera locally backwards by any amount, then use
GetScreenXFrom3D (GetObjectMeshSizeMinX(objectnumber,1),GetObjectY(objectnumber),GetObjectZ(objectnumber))
it all works fine and you get the screen coord of the minimum x position of the object. Now slowly move the camera locally along the Z axis towards the object and keep calling the above line of code......the X coord isn't changing, even though the left most position of the object BLANTANTLY is.
All other examples of this seems to work fine, but just moving the camera locally doesn't seem to work???