Yep, it doesnt work for me either. Also through testing I found something else interesting. I made a new camera with an ID of 1, and set that to be the current camera. Then I used the cube from your example also with an ID of 1. If you pressed left or right, the cube would spin accordingly instead of the camera. And if the cube and new camera had different IDs, the same behavior would occur as in your example. Here is the code that generates the spinning cube instead of spinning camera:
#include "DarkSDK.h"
void DarkSDK(void)
{
dbSyncOn();
dbMakeCamera(1);
dbSetCurrentCamera(1);
dbMakeObjectCube(1, 10);
while(LoopSDK())
{
if(dbEscapeKey())
break;
if(dbLeftKey())
dbTurnCameraLeft(1, 1.0f);
if(dbRightKey())
dbTurnCameraRight(1, 1.0f);
dbSync();
}
dbDeleteCamera(1);
dbDeleteObject(1);
}