Hi, just contributing to this issue. Loading DayZ for the first time displays the user interface at a ridiculously low resolution. After a while of struggling to read the menu I changed the gameplay resolution before I realized that the menu had its own resolution setting. Now that I updated it, things seem to be fine. It's difficult to click around the menu as your pointer doesn't align with your mouse scrolling due to the low resolution.
I have an Nvidia GForce GT 525M and my desktop resolution is 1366x768. Could it be because the user is running a desktop resolution that isn't supported in-game?