Sitecore goals for Media Item don't affect engagement value

Question

I use Sitecore 7.2 revision 140526 + DMS. I'm trying to assign goal to the media item (PDF). When I try to download this media item the goal get registered in the PageEvents table but Engagement Value of the visit does not change. I found following code inside StartTrackingProcessor:

Tracker.CurrentPage.OnCancel += (EventHandler)((obj, args) =>
{
    AcceptChangesArgs acceptChangesArgs = args as AcceptChangesArgs;
    if (acceptChangesArgs == null)
        return;
    VisitorDataSet.VisitsRow currentVisit = acceptChangesArgs.Visitor.CurrentVisit;
    if (currentVisit == null)
        return;

    Tracker.CurrentPage.RollBackValue(pageEventData, currentVisit);
});

This code prevents engagement value from increasing for the pages that have been cancelled somewhere in the pipeline. And then I found the code that cancel the page in the Sitecore.Analytics.RobotDetection.Media.MediaRequestEventHandler whech is enabled by Sitecore.Analytics.RobotDetection.config:

using (new ContextItemSwitcher(obj))
{
    try
    {
        this.StartTracking();
        VisitorDataSet.PagesRow previousPage = Tracker.CurrentVisit.PreviousPage;
        if (previousPage != null)
        {
            Guid pageId = previousPage.PageId;
            foreach (VisitorDataSet.PageEventsRow pageEventsRow in Enumerable.ToArray<VisitorDataSet.PageEventsRow>(Tracker.CurrentPage.PageEvents))
                pageEventsRow.PageId = pageId;


            Tracker.CurrentPage.Cancel();
        }
        this.EndTracking();
    }
    catch (Exception ex)
    {
        Log.Error("Media request analytics failed", ex, this.GetType());
    }
}

So this MediaRequestEventHandler cancels the page and therefore engagement value does not increase. I can override this behavior or disable RobotDetection.config but I want to understand the consequences and why it was done this way and I know there are recommendations not to disable Sitecore.Analytics.RobotDetection.config

So my question: what is the best way to assign points to the visit for media item download?

Answer 1

For those who might come across the same problem here is the response from sitecore support. This behavior was reported as a bug and as a workaround they suggested to comment out following lines in Sitecore.Analytics.RobotDetection.config:

<event name="media:request">
    <handler patch:instead="*[@type='Sitecore.Analytics.Media.MediaRequestEventHandler, Sitecore.Analytics']" type="Sitecore.Analytics.RobotDetection.Media.MediaRequestEventHandler, Sitecore.Analytics.RobotDetection" method="OnMediaRequest"/>
</event>