Errors off hitters cards??

This has probably been answered before but:

A 1-6 was originally rolled on Jeff Bagwell's card which resulted in a double (no field indicated). There was a man on first and second. Bagwell ended up scoring on the play with an error charged to the CF'er. I assume in real life this simulates the CF'er throwing the ball into the stands or something along that line, which I would not question if it resulted from an "X" chart reading.

My question is: by what gaming mechanism is this result triggered?

Is there some super duper advanced rules?

An open-ended double allows the runner on first to attempt to score (speed plus 2 for nor being held minus/plus CF's arm), but also requires a roll for CF's error rating. Defending manager can elect to cut the throw and attempt to get the batter if he tries to take third (batter's speed minus 5), allowing the first-base runner to score automatically without an error chance. A two-base error allows batter to score as well. In close plays at the plate, catcher's blocking ability (essentially his defense rating) comes into play also. HAL makes the decision on whether to run/cut/etc.

Tim,

You need to get yourself the CD-Rom of the game.
In this version of the game, the manager strategy of Base Running has an effect on the scenario you present.
In the CD-Rom game, in-game managing allows you to make the decision on whether you try to run for the extra base or not and send a trailing runner or not, and for the defensive team to throw for the lead runner or trailing runner.
Thus, with the max rule setting of "allowing for throwing errors," which the Online version has selected, there is the opportunity for the OF to receive an error in this fashion - even off the hitter's card.

So the answer to my question is:

We are consulting the CF error rating chart in this instance.