problem with a drag command

The drag command in testcomplete needs co-ordinates.  You need to know the object to be dragged and the destination and that is, for the Drag method, co-ordinate based.

but!  Never fear... I've got a code for that.

In Javascript:

function dragCalculatedDistance(startObject, destinationObject) {
    var startPoint, targetPoint, dragX, dragY;
    // Drag from the center of object A to the center of object B

    startPoint = startObject.WindowToScreen(startObject.Width/2, startObject.Height/2);
    targetPoint = destinationObject.WindowToScreen(destinationObject.Width/2, destinationObject.Height/2);

    dragX = targetPoint.X - startPoint.X;
    dragY = targetPoint.Y - startPoint.Y;

    startObject.Drag(-1, -1, dragX, dragY); 
}

As noted in the comments, this will drag from roughly the center of the starting object to the center of the destination object.