Just wanted to verify to other Hot Line Owners that the OP (jefwv - and others) are correct in that the machine's Ball Gate does have the carry over feature from the factory and there is no Jones Plug to change this feature.
It is normal for the Ball Gate when lit to stay open after the game ends if the ball does not go through the gate to deactivate the shooter lane switch during a game.
I thought there was something wrong with my machine as well, but found this old thread and as newmantjn stated that after fixing his broken wire his game works the same as the rest of ours. Rolf-Martin-062 did a lot of research as well and not owning the game at the time came to the same conclusion.
Finally, as stated by another poster please make sure to document any changes you make to this feature if you wish to change it whether cutting or disabling a wire, so that the future owner can decide easily if he wants to return the machine to it's factory intended carry over feature. Personally I am keeping the feature on my game factory original.
Ken 
