I just meant gameplay wise. It makes no sense to me.
Its a replication of the Williams Multigame CP that allowed Robotron, Defender, Joust, Stargate, Bubbles and Splat! to be played in a single cabinet.
Edit: Looking at that image the button layout is similar to your model. Im guessing if you are stood up your forearms are at an angle and so there must not be an issue with touching the lower buttons. However as yours is a cocktail your forearms are more likely to be parallel to the panel and they may be in the way.
Looking at Spacies panel it appears that this may be the case as it seems he has moved the 'black' button to the right.
As Lilwolf said, the onlyway to be sure is to do a card/hardboard mockup with the controls in place. Install the components in the card/hardboard and then mount it to something at the same height and angle that you are planning on having your CP. Sit on a stool or whatever you intend on using and then see if there are any issues with the button placement. Thats the only way to be sure.