Chase re-joined his old club last month for the rest of 2016.
With injury-hit Cas forced to use hookers and props in the halves at times this season to partner Luke Gale, Chase gives the Tigers a different option at stand-off.
Dorn told Love Rugby League that the former Man of Steel has been good for the club.
“Rangi’s been good because we were saying when he first came here if there’s any style of play that suits us it’s his style,” he said.
“It’s the way we play we like to shift the ball around and we like to take the opportunities to not give teams a second to breath in terms of how they defend.
“We don’t even set up time or whatever so he’s an ideal half in the way we like to play our game.
“I think he’s fit in really well. We’ve got some good players like myself and Galey who are good communicators with Rangi and he’s found it easy.
“I think weve tried to really simplify his game in terms of the amount of plays he’s got to learn.
“We’ve only given him three plays really thats he’s got to nail down, other than that I think hell be really good for us and he can give us that spark that we need for the run at the four.”