Arkin also had a high snap that Orton had to jump for.
Later in the walkthrough, Arkin snapped another ball, out of the shotgun, over the head of Stephen McGee.
Following the second shotgun snap over Orton, coach Jason Garrett said, "Snap it between the one and the eight. You can do it."
When asked about his center problems by reporters, Garrett said, "I think you have a little knowledge after watching that walkthrough. We cued the circus music a couple different times during that walkthrough."
The Cowboys have endured issues at center after releasing Andre Gurode last summer. Phil Costa is the starter but he struggled at times last season. This training camp the Cowboys wanted a competition at the center spot, adding Kevin Kowalski to the mix with Costa.
With Kowalski sidelined due to an ankle injury, the Cowboys gave guard Harland Gunn a shot at the position. When that didn't work out, Arkin, a guard, was moved to center.
Garrett said there was some thoughts about adding a veteran center, but for now the Cowboys are sticking with their current roster. Jason Brown, Scott Mruczkowski and Jeff Faine are some veteran centers on the market.
"When the ball isn't handled the right way it really slows down the whole process, makes everything look really sluggish and really sloppy," Garrett said. "The thing we have to remind ourselves as coaches is what the situation is and it's really having to do with one position and a very important position and a very important process the snap from the center to the quarterback, we're trying to train a lot of different guys as you know we've had a lot of injuries in there."