When you disconnect from a server, the disconnect button as well as the other buttons are scattered around the different screens - there's no consistency in the buttons' placement.
- Legacy ID
Whether it's on the left or right is irrelevant, but a standard should be chosen for your UI and implemented throughout the application. Negative actions (Disconnect, Cancel, Back) on the left; positive actions (OK, Accept, Continue) on the right, or vice versa. Choose one paradigm, and stick with it everywhere, and you'll greatly improve the user experience in the menus.