I plugged the UDOO Neo to my Macbook Pro with USB to micro USB cable, it turns on and loads UDOObuntu; I can see the desktop with the micro HDMI cable plugged to a monitor. I then tried to connect via SSH, and I'm able to log in and see the contents of the microSD. Anyway, I couldn't use succesfully VNC Viewer: I input the IP address and login password, and a completely grey desktop appears, without controls. What can be the issue? See attached screenshot
It takes a while for VNC/X to start-up. On the order of 1-2 minutes. I saw a similar grey screen, but it did eventually resolve to a linux desktop interface. If yours is like mine, the orange SDCard led was on almost solid while the desktop loaded. (I also saw OOM messages to the console serial port.) Note, that I have the Basic version.