I've seen some videos (even the "GenCon Klask Finals" video) where the player puts the ball in the corner on kickoff, and then guides it out to their side of the field with the striker before hitting the ball again across the center line. We have always played that you must hit the ball from the corner so that it crosses the center line without any additional hits/touches.
The rules are not explicitly clear on this, but it seems like if you're allowed to guide/hit the ball multiple times after kickoff before it crosses the center line, there is no point is starting from the corner.
We emailed the designer, and he confirmed that the intention is to hit the ball across the center line from the corner on the kickoff. (However, he did admit that the rules are not clear, and that the players can use whatever method they both agree on.)
Just wanted to put this information out there. Hopefully future editions of the game will have this point clarified in the rules.