The end door on this car is closed! Wonder why.
The Ventures have mostly open-gangway ends that in normal operation can only interface with other Venture cars. The NEC test train is only using one single Venture car: one end with a conventional vestibule that can interface with the Amfleet, and the regular open-gangway end that has to be temp-plugged with a pane of sheet metal because there isn't another Venture car on the train to hook it to. That's strictly for the test train; they won't operate with the metal plugs like that in regular service.
The Caltrans/
San Joaquins order of Ventures are configured as 7-car sets. Cars #1 and #7 have conventional vestibules on the outermost-facing ends to interface with an Amfleet, Viewliner, or other generic car...but all ends of Cars #2-6 and the inner ends of #1 & #7 have the open-gangway plugs that can only interface with another Venture. They use conventional AAR couplers, but the gangway mechanism is hard-bolted and needs yard staffers with tools to separate.
VIA Rail's order of Ventures are configured as 5-car sets. Cars #1 and #5 have conventional vestibules on the outermost-facing ends, with everything in-between being the hard-coupled open gangway.
The Brightline order of Ventures are configured as smaller 4-car sets. Cars #1 and #4 have conventional vestibules on the outermost-facing ends, with everything in-between being the hard-coupled open gangway.
The Midwest Ventures are configured even smaller as married-pair sets: hard-coupled open gangways between the members of each pair of cars but then conventional vestibules between pairs.
Amtrak hasn't specified what the default config is going to be for the
Northeast Regional order; that's not due to be formally specced until August. It's predicted to be more than the Midwest's 2 cars per set but less than Caltrans' 7 cars per set (4 or 6 cars are likely since the longest
Northeast Regional platforms run 12 cars and thus it's extremely likely they'll chunk 'em in intermediate-size divisors of 12). The option orders for NYSDOT/Empire Corridor, PennDOT/Keystone Corridor, and NNEPRA/
Downeaster can be further customized by desired # of cars per set, and haven't had any quantities specced yet.