All launch cars have this fitted, mine did indeed break the stop off the gear wheel. A correctly positioned small nut and bolt through the body of the gear wheel sorted the problem until a replacement could be found.
The early type Cruise control actuator from the E39 is the exact same item for those who are looking for a replacement.
One here for example
http://www.ebay.co.uk/itm/M18799-BMW...0AAOSwZ8ZW4JOS