All the graphics drivers for your laptop come from the laptop manufacturer...not from AMD. There are no drivers for Mobility Vega or the Radeon M535 on the site. These are the responsibility of the laptop manufacturer (OEM). Download Drivers and Manuals | Acer Official Site
Dayz is a experimental/beta game...there will always be issues when these games come out...and fixed with future game updates. You might report this to the game developers.