mapNavigation.buttons y position
There is no "y" property for mapNavigation.buttons, so it is not possible to adjust precisely y position.
Josh McCullough commented
@Torstein - thanks, that works. But it would be nice to be able to offset the entire zoom panel like you can with the legend panel. See the original thread, here: http://forum.highcharts.com/highmaps-usage-f14/can-t-adjust-mapnavigation-buttons-y-location-t32460/
The cause of this is that the zoom-in and zoom-out buttons have individual y offsets, so instead of setting it in the general buttonOptions, you should set it in the individual button options: http://jsfiddle.net/highcharts/1tpa8rm0/6/
Kacper Madej commented
Precise positioning is not possible by default, but can be unlock that functionality writting wrapper or using one in this example.